服务器内部错误 CDbConnection failed to open the DB connection.

服务器内部错误 CDbConnection failed to open the DB connection. 当前网页服务器在处理您的请求时,发生了一个内部错误. 请将此问题报告给服务器管理员 the webmaster.  ## 我的这个IIS 是关闭状态  ## 这个网站依旧报这个错误  #在服务器里用浏览器访问正常  #感觉这个报错 和 IIS无关和系统有关 # #系统windows 2008 程序是html ,里面的内容就是上面最后一张图的内容“新建文本文档”，没有连接数据库，没有JS，没有css,就是这几个字，怪异的事，把IIS服务关了，依旧有这个报错 ---- 我写的文章有兴趣的看看吧，很怪异 服务器内部错误 CDbConnection failed to open the DB connection. https://blog.csdn.net/cplvfx/article/details/103716312

openoffice Linux注册

rpm已装，也装了freedesktop桌面，公司服务器linux centos64bit没有界面，就putty，ssh，ps-ef|grep soffice可以看到3个线程已启动，/bin/sh /opt/openoffice4/program/soffice --headless --accept="socket,host=127.0.0.1,port=8100;up;" --nofirststartwizard & 也能出来类似[1] 12751 ，但程序运行起来就报错，一直都是这个错Java.net.ConnectionException:connection failed:socket,host=local host,port=8100,tcpNoDelay=1:Java.net.connectionexception:connection refused…swftools都装好了flex paper也都调好了，这个doc2pdf出不来后面都没戏，另外，我用本地测试open office win版都是一次性pass的，估计是Linux无界面无法跳过注册？

公司GPU服务器两块nvidia 1080ti显卡，centos系统，无法startx

显卡驱动已经安装 按照网上教程装各种图形界面 startx都报错 相关错误日志和错误提示 ———————————— /var/log/Xorg.0.log日志如下 [ 883.706] X.Org X Server 1.19.5 Release Date: 2017-10-12 [ 883.707] X Protocol Version 11, Revision 0 [ 883.707] Build Operating System: 3.10.0-693.17.1.el7.x86_64 [ 883.708] Current Operating System: Linux yikumed-GPU 3.10.0-862.14.4.el7.x86_64 #1 SMP Wed Sep 26 15:12:11 UTC 2018 x86_64 [ 883.708] Kernel command line: BOOT_IMAGE=/vmlinuz-3.10.0-862.14.4.el7.x86_64 root=/dev/mapper/centos_yikumed--gpu-root ro crashkernel=auto rd.lvm.lv=centos_yikumed-gpu/root rd.lvm.lv=centos_yikumed-gpu/swap rhgb quiet LANG=zh_CN.UTF-8 [ 883.709] Build Date: 29 October 2018 03:33:19PM [ 883.709] Build ID: xorg-x11-server 1.19.5-5.1.el7_5.0.1 [ 883.710] Current version of pixman: 0.34.0 [ 883.710] Before reporting problems, check http://wiki.x.org to make sure that you have the latest version. [ 883.710] Markers: (--) probed, (**) from config file, (==) default setting, (++) from command line, (!!) notice, (II) informational, (WW) warning, (EE) error, (NI) not implemented, (??) unknown. [ 883.712] (==) Log file: "/var/log/Xorg.0.log", Time: Sat Nov 3 14:31:06 2018 [ 883.713] (==) Using config directory: "/etc/X11/xorg.conf.d" [ 883.713] (==) Using system config directory "/usr/share/X11/xorg.conf.d" [ 883.714] (==) No Layout section. Using the first Screen section. [ 883.714] (==) No screen section available. Using defaults. [ 883.714] (**) |-->Screen "Default Screen Section" (0) [ 883.714] (**) | |-->Monitor "<default monitor>" [ 883.714] (==) No monitor specified for screen "Default Screen Section". Using a default monitor configuration. [ 883.714] (==) Automatically adding devices [ 883.714] (==) Automatically enabling devices [ 883.714] (==) Automatically adding GPU devices [ 883.714] (==) Automatically binding GPU devices [ 883.714] (==) Max clients allowed: 256, resource mask: 0x1fffff [ 883.714] (==) FontPath set to: catalogue:/etc/X11/fontpath.d, built-ins [ 883.714] (==) ModulePath set to "/usr/lib64/xorg/modules" [ 883.714] (II) The server relies on udev to provide the list of input devices. If no devices become available, reconfigure udev or disable AutoAddDevices. [ 883.714] (II) Loader magic: 0x557fe15eb020 [ 883.714] (II) Module ABI versions: [ 883.714] X.Org ANSI C Emulation: 0.4 [ 883.714] X.Org Video Driver: 23.0 [ 883.714] X.Org XInput driver : 24.1 [ 883.714] X.Org Server Extension : 10.0 [ 883.714] (II) xfree86: Adding drm device (/dev/dri/card0) [ 883.715] (II) xfree86: Adding drm device (/dev/dri/card1) [ 883.743] (--) PCI: (0:23:0:0) 10de:1b06:1028:3600 rev 161, Mem @ 0x91000000/16777216, 0x380060000000/268435456, 0x380070000000/33554432, I/O @ 0x00005000/128, BIOS @ 0x????????/524288 [ 883.743] (--) PCI:*(0:115:0:0) 10de:1b06:1028:3600 rev 161, Mem @ 0xc4000000/16777216, 0xb0000000/268435456, 0xc0000000/33554432, I/O @ 0x00009000/128, BIOS @ 0x????????/524288 [ 883.743] (II) LoadModule: "glx" [ 883.744] (II) Loading /usr/lib64/xorg/modules/extensions/libglx.so [ 883.745] (II) Module glx: vendor="X.Org Foundation" [ 883.745] compiled for 1.19.5, module version = 1.0.0 [ 883.745] ABI class: X.Org Server Extension, version 10.0 [ 884.113] (==) Matched nouveau as autoconfigured driver 0 [ 884.113] (==) Matched nouveau as autoconfigured driver 1 [ 884.113] (==) Matched nouveau as autoconfigured driver 2 [ 884.113] (==) Matched modesetting as autoconfigured driver 3 [ 884.113] (==) Matched fbdev as autoconfigured driver 4 [ 884.113] (==) Matched vesa as autoconfigured driver 5 [ 884.113] (==) Assigned the driver to the xf86ConfigLayout [ 884.113] (II) LoadModule: "nouveau" [ 884.113] (II) Loading /usr/lib64/xorg/modules/drivers/nouveau_drv.so [ 884.114] (II) Module nouveau: vendor="X.Org Foundation" [ 884.114] compiled for 1.19.3, module version = 1.0.13 [ 884.114] Module class: X.Org Video Driver [ 884.114] ABI class: X.Org Video Driver, version 23.0 [ 884.114] (II) LoadModule: "modesetting" [ 884.115] (II) Loading /usr/lib64/xorg/modules/drivers/modesetting_drv.so [ 884.115] (II) Module modesetting: vendor="X.Org Foundation" [ 884.115] compiled for 1.19.5, module version = 1.19.5 [ 884.115] Module class: X.Org Video Driver [ 884.115] ABI class: X.Org Video Driver, version 23.0 [ 884.115] (II) LoadModule: "fbdev" [ 884.115] (II) Loading /usr/lib64/xorg/modules/drivers/fbdev_drv.so [ 884.115] (II) Module fbdev: vendor="X.Org Foundation" [ 884.115] compiled for 1.19.3, module version = 0.4.3 [ 884.115] Module class: X.Org Video Driver [ 884.115] ABI class: X.Org Video Driver, version 23.0 [ 884.115] (II) LoadModule: "vesa" [ 884.116] (II) Loading /usr/lib64/xorg/modules/drivers/vesa_drv.so [ 884.116] (II) Module vesa: vendor="X.Org Foundation" [ 884.116] compiled for 1.19.3, module version = 2.3.2 [ 884.116] Module class: X.Org Video Driver [ 884.116] ABI class: X.Org Video Driver, version 23.0 [ 884.116] (II) NOUVEAU driver [ 884.116] (II) NOUVEAU driver for NVIDIA chipset families : [ 884.116] RIVA TNT (NV04) [ 884.116] RIVA TNT2 (NV05) [ 884.116] GeForce 256 (NV10) [ 884.116] GeForce 2 (NV11, NV15) [ 884.116] GeForce 4MX (NV17, NV18) [ 884.116] GeForce 3 (NV20) [ 884.116] GeForce 4Ti (NV25, NV28) [ 884.116] GeForce FX (NV3x) [ 884.116] GeForce 6 (NV4x) [ 884.116] GeForce 7 (G7x) [ 884.116] GeForce 8 (G8x) [ 884.116] GeForce GTX 200 (NVA0) [ 884.117] GeForce GTX 400 (NVC0) [ 884.117] (II) modesetting: Driver for Modesetting Kernel Drivers: kms [ 884.117] (II) FBDEV: driver for framebuffer: fbdev [ 884.117] (II) VESA: driver for VESA chipsets: vesa [ 884.117] (++) using VT number 2 [ 884.120] (EE) [drm] Failed to open DRM device for (null): -2 [ 884.120] (EE) [drm] Failed to open DRM device for (null): -2 [ 884.120] (EE) [drm] Failed to open DRM device for (null): -2 [ 884.120] (EE) [drm] Failed to open DRM device for (null): -2 [ 884.120] (EE) [drm] Failed to open DRM device for (null): -2 [ 884.120] (EE) [drm] Failed to open DRM device for pci:0000:73:00.0: -2 [ 884.120] (EE) [drm] Failed to open DRM device for pci:0000:73:00.0: -2 [ 884.120] (EE) [drm] Failed to open DRM device for pci:0000:73:00.0: -2 [ 884.121] (WW) Falling back to old probe method for modesetting [ 884.121] (II) Loading sub module "fbdevhw" [ 884.121] (II) LoadModule: "fbdevhw" [ 884.121] (II) Loading /usr/lib64/xorg/modules/libfbdevhw.so [ 884.121] (II) Module fbdevhw: vendor="X.Org Foundation" [ 884.121] compiled for 1.19.5, module version = 0.0.2 [ 884.121] ABI class: X.Org Video Driver, version 23.0 [ 884.121] (EE) open /dev/fb0: No such file or directory [ 884.121] (WW) Falling back to old probe method for fbdev [ 884.121] (II) Loading sub module "fbdevhw" [ 884.121] (II) LoadModule: "fbdevhw" [ 884.122] (II) Loading /usr/lib64/xorg/modules/libfbdevhw.so [ 884.122] (II) Module fbdevhw: vendor="X.Org Foundation" [ 884.122] compiled for 1.19.5, module version = 0.0.2 [ 884.122] ABI class: X.Org Video Driver, version 23.0 [ 884.122] (EE) open /dev/fb0: No such file or directory [ 884.122] vesa: Ignoring device with a bound kernel driver [ 884.122] (WW) Falling back to old probe method for vesa [ 884.122] (EE) Screen 0 deleted because of no matching config section. [ 884.122] (II) UnloadModule: "modesetting" [ 884.122] (EE) Screen 0 deleted because of no matching config section. [ 884.122] (II) UnloadModule: "fbdev" [ 884.122] (II) UnloadSubModule: "fbdevhw" [ 884.122] (EE) Screen 0 deleted because of no matching config section. [ 884.122] (II) UnloadModule: "vesa" [ 884.122] (EE) Device(s) detected, but none match those in the config file. [ 884.122] (EE) Fatal server error: [ 884.122] (EE) no screens found(EE) [ 884.122] (EE) Please consult the The X.Org Foundation support at http://wiki.x.org for help. [ 884.122] (EE) Please also check the log file at "/var/log/Xorg.0.log" for additional information. [ 884.122] (EE) [ 884.124] (EE) Server terminated with error (1). Closing log file. —————————————————————————— 运行startx错误提示 xauth: file /root/.serverauth.3246 does not exist xauth: (stdin):2: unknown command "8236e144403225f38c522dc0f25435bd" xauth: (stdin):3: unknown command "8236e144403225f38c522dc0f25435bd" X.Org X Server 1.19.5 Release Date: 2017-10-12 X Protocol Version 11, Revision 0 Build Operating System: 3.10.0-693.17.1.el7.x86_64 Current Operating System: Linux yikumed-GPU 3.10.0-862.14.4.el7.x86_64 #1 SMP Wed Sep 26 15:12:11 UTC 2018 x86_64 Kernel command line: BOOT_IMAGE=/vmlinuz-3.10.0-862.14.4.el7.x86_64 root=/dev/mapper/centos_yikumed--gpu-root ro crashkernel=auto rd.lvm.lv=centos_yikumed-gpu/root rd.lvm.lv=centos_yikumed-gpu/swap rhgb quiet LANG=zh_CN.UTF-8 Build Date: 29 October 2018 03:33:19PM Build ID: xorg-x11-server 1.19.5-5.1.el7_5.0.1 Current version of pixman: 0.34.0 Before reporting problems, check http://wiki.x.org to make sure that you have the latest version. Markers: (--) probed, (**) from config file, (==) default setting, (++) from command line, (!!) notice, (II) informational, (WW) warning, (EE) error, (NI) not implemented, (??) unknown. (==) Log file: "/var/log/Xorg.0.log", Time: Sat Nov 3 12:39:52 2018 (==) Using config directory: "/etc/X11/xorg.conf.d" (==) Using system config directory "/usr/share/X11/xorg.conf.d" vesa: Ignoring device with a bound kernel driver (EE) Fatal server error: (EE) no screens found(EE) (EE) Please consult the The X.Org Foundation support at http://wiki.x.org for help. (EE) Please also check the log file at "/var/log/Xorg.0.log" for additional information. (EE) (EE) Server terminated with error (1). Closing log file. xinit: giving up xinit: unable to connect to X server: Connection refused xinit: server error

linux调用swt网页截屏

在linux weblogic 服务器调用swt进行网页截屏时报错，困扰了大半个月了，还请各位朋友帮帮~~， 使用的是 DJNativeSwing-SWT.jar DJNativeSwing.jar swt.jar jna-4.0.0.jar NativeSwing[1]: Exception in thread "main" java.lang.reflect.InvocationTargetException NativeSwing[1]: at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) NativeSwing[1]: at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) NativeSwing[1]: at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) NativeSwing[1]: at java.lang.reflect.Method.invoke(Method.java:597) NativeSwing[1]: at chrriis.common.NetworkURLClassLoader.main(NetworkURLClassLoader.java:96) NativeSwing[1]: Caused by: org.eclipse.swt.SWTError: No more handles [gtk_init_check() failed] NativeSwing[1]: at org.eclipse.swt.SWT.error(Unknown Source) NativeSwing[1]: at org.eclipse.swt.widgets.Display.createDisplay(Unknown Source) NativeSwing[1]: at org.eclipse.swt.widgets.Display.create(Unknown Source) NativeSwing[1]: at org.eclipse.swt.graphics.Device.<init>(Unknown Source) NativeSwing[1]: at org.eclipse.swt.widgets.Display.<init>(Unknown Source) NativeSwing[1]: at chrriis.dj.nativeswing.swtimpl.NativeInterface$OutProcess.runNativeSide(NativeInterface.java:999) NativeSwing[1]: at chrriis.dj.nativeswing.swtimpl.NativeInterface.main(NativeInterface.java:1096) NativeSwing[1]: ... 5 more NativeSwing[2]: Exception in thread "main" java.lang.reflect.InvocationTargetException NativeSwing[2]: at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) NativeSwing[2]: at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) NativeSwing[2]: at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) NativeSwing[2]: at java.lang.reflect.Method.invoke(Method.java:597) NativeSwing[2]: at chrriis.common.NetworkURLClassLoader.main(NetworkURLClassLoader.java:96) NativeSwing[2]: Caused by: org.eclipse.swt.SWTError: No more handles [gtk_init_check() failed] NativeSwing[2]: at org.eclipse.swt.SWT.error(Unknown Source) NativeSwing[2]: at org.eclipse.swt.widgets.Display.createDisplay(Unknown Source) NativeSwing[2]: at org.eclipse.swt.widgets.Display.create(Unknown Source) NativeSwing[2]: at org.eclipse.swt.graphics.Device.<init>(Unknown Source) NativeSwing[2]: at org.eclipse.swt.widgets.Display.<init>(Unknown Source) NativeSwing[2]: at chrriis.dj.nativeswing.swtimpl.NativeInterface$OutProcess.runNativeSide(NativeInterface.java:999) NativeSwing[2]: at chrriis.dj.nativeswing.swtimpl.NativeInterface.main(NativeInterface.java:1096) NativeSwing[2]: ... 5 more NativeSwing[3]: Exception in thread "main" java.lang.reflect.InvocationTargetException NativeSwing[3]: at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) NativeSwing[3]: at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) NativeSwing[3]: at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) NativeSwing[3]: at java.lang.reflect.Method.invoke(Method.java:597) NativeSwing[3]: at chrriis.common.NetworkURLClassLoader.main(NetworkURLClassLoader.java:96) NativeSwing[3]: Caused by: org.eclipse.swt.SWTError: No more handles [gtk_init_check() failed] NativeSwing[3]: at org.eclipse.swt.SWT.error(Unknown Source) NativeSwing[3]: at org.eclipse.swt.widgets.Display.createDisplay(Unknown Source) NativeSwing[3]: at org.eclipse.swt.widgets.Display.create(Unknown Source) NativeSwing[3]: at org.eclipse.swt.graphics.Device.<init>(Unknown Source) NativeSwing[3]: at org.eclipse.swt.widgets.Display.<init>(Unknown Source) NativeSwing[3]: at chrriis.dj.nativeswing.swtimpl.NativeInterface$OutProcess.runNativeSide(NativeInterface.java:999) NativeSwing[3]: at chrriis.dj.nativeswing.swtimpl.NativeInterface.main(NativeInterface.java:1096) NativeSwing[3]: ... 5 more java.lang.RuntimeException: java.net.SocketException: Connection reset NativeInterface.open:java.lang.RuntimeException: java.net.SocketException: Connection reset at chrriis.dj.nativeswing.swtimpl.OutProcessSocketsMessagingInterface.openChannel(OutProcessSocketsMessagingInterface.java:64) at chrriis.dj.nativeswing.swtimpl.MessagingInterface.initialize(MessagingInterface.java:51) at chrriis.dj.nativeswing.swtimpl.OutProcessSocketsMessagingInterface.<init>(OutProcessSocketsMessagingInterface.java:29) at chrriis.dj.nativeswing.swtimpl.OutProcessSocketsMessagingInterface$SwingOutProcessSocketsMessagingInterface.<init>(OutProcessSocketsMessagingInterface.java:151) at chrriis.dj.nativeswing.swtimpl.NativeInterface$OutProcess.createOutProcessMessagingInterface(NativeInterface.java:830) at chrriis.dj.nativeswing.swtimpl.NativeInterface$OutProcess.createOutProcessCommunicationChannel(NativeInterface.java:540) at chrriis.dj.nativeswing.swtimpl.NativeInterface.open(NativeInterface.java:244) at sunline.common.logic.filter.FileFilter.doFilter(FileFilter.java:103) at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:60) at sunline.common.logic.filter.EncodingFilter.doFilter(EncodingFilter.java:39) at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:60) at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.wrapRun(WebAppServletContext.java:3739) at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.run(WebAppServletContext.java:3705) at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:321) at weblogic.security.service.SecurityManager.runAs(SecurityManager.java:120) at weblogic.servlet.internal.WebAppServletContext.securedExecute(WebAppServletContext.java:2282) at weblogic.servlet.internal.WebAppServletContext.execute(WebAppServletContext.java:2181) at weblogic.servlet.internal.ServletRequestImpl.run(ServletRequestImpl.java:1491) at weblogic.work.ExecuteThread.execute(ExecuteThread.java:256) at weblogic.work.ExecuteThread.run(ExecuteThread.java:221) Caused by: java.net.SocketException: Connection reset at java.net.SocketInputStream.read(SocketInputStream.java:168) at java.io.BufferedInputStream.fill(BufferedInputStream.java:218) at java.io.BufferedInputStream.read1(BufferedInputStream.java:258) at java.io.BufferedInputStream.read(BufferedInputStream.java:317) at java.io.ObjectInputStream$PeekInputStream.read(ObjectInputStream.java:2266) at java.io.ObjectInputStream$PeekInputStream.readFully(ObjectInputStream.java:2279) at java.io.ObjectInputStream$BlockDataInputStream.readShort(ObjectInputStream.java:2750) at java.io.ObjectInputStream.readStreamHeader(ObjectInputStream.java:780) at java.io.ObjectInputStream.<init>(ObjectInputStream.java:280) at chrriis.dj.nativeswing.swtimpl.OutProcessSocketsMessagingInterface.openChannel(OutProcessSocketsMessagingInterface.java:62) ... 19 more

linux文件传输，初学，请大家帮忙，谢谢

我 已经连接上了服务端，它有怎样的信息传输功能呢？ #include <pthread.h> #include <signal.h> #include <stdlib.h> #include <stdio.h> #include <sys/types.h> #include <sys/socket.h> #include <netinet/in.h> #include <sys/select.h> #include <errno.h> #include <fcntl.h> #include <sys/stat.h> #include <string.h> #include <unistd.h> #include <sys/time.h> #include <arpa/inet.h> #include "serv_client.h" int main(int argc,char** argv) { int sockfd; int clientfd; uint16_t port; int ret; pid_t pid; struct sockaddr_in server_addr; if ( 2 != argc ){ printf("usage:command listen_port\n"); return -1; } port = atoi(argv[1]); server_addr.sin_family = AF_INET; server_addr.sin_addr.s_addr = INADDR_ANY; server_addr.sin_port = htons(port); sockfd = socket(PF_INET,SOCK_STREAM,0); if (sockfd < 0) { perror("open data stream socket failed!\n"); return -1; } ret = bind(sockfd,(struct sockaddr *)&server_addr,sizeof(server_addr)); if(ret < 0) { perror("bind data socket failed!\n"); return -1; } ret = listen(sockfd, SOMAXCONN ); if( ret < 0) { perror("listening data stream failed!\n"); return -1; } printf("Waiting for client conneciton...\n"); while(1) { clientfd = accept(sockfd, NULL, NULL); if( clientfd < 0) { perror("accept data connection error!\n"); return -1; } pid = fork(); if ( pid < 0 ){ perror("fork error!\n"); } if ( 0 == pid ){ //chid process printf("one client come ...\n"); serv_client(clientfd); return 0; } close(clientfd); } } #include <pthread.h> #include <signal.h> #include <stdlib.h> #include <stdio.h> #include <sys/types.h> #include <sys/socket.h> #include <netinet/in.h> #include <errno.h> #include <fcntl.h> #include <sys/stat.h> #include <string.h> #include <dirent.h> #include <unistd.h> #include <netdb.h> #include <sys/time.h> #include "client_process.h" void usage() { printf("command ip_addr port\n"); } int main(int argc,char **argv) { struct sockaddr_in server; int sockfd; int port; int ip_addr; int ret; if ( 3 != argc ){ usage(); return -1; } sockfd = socket(PF_INET, SOCK_STREAM , 0); if(sockfd < 0) { perror("data stream socket create failed!\n"); return -1; } server.sin_family = AF_INET; port = atoi(argv[2]); server.sin_port = htons(port); ret = inet_pton(AF_INET, argv[1], &server.sin_addr.s_addr); if ( ret <=0 ){ printf("your ip address is unvalide!\n"); usage(); return -1; } ret = connect(sockfd,(struct sockaddr*) &server,sizeof(struct sockaddr_in)); if(ret < 0) { perror("data connection is failed!\n"); return -1; } printf("connect to server successfully!\n"); clinet_process( sockfd ); }

linux系统下使用snmpset命令始终报错，，，

[root@localhost 桌面]# snmpset -v2c -c public -On localhost system.sysName.0 s linux Error in packet. Reason: noAccess Failed object: .1.3.6.1.2.1.1.5.0 始终处于这个错误，请各路大神帮帮我，感激不尽，，，，我的conmpd.conf文件是： ############################################################################### # # snmpd.conf: # An example configuration file for configuring the ucd-snmp snmpd agent. # ############################################################################### # # This file is intended to only be as a starting point. Many more # configuration directives exist than are mentioned in this file. For # full details, see the snmpd.conf(5) manual page. # # All lines beginning with a '#' are comments and are intended for you # to read. All other lines are configuration commands for the agent. ############################################################################### # Access Control ############################################################################### # As shipped, the snmpd demon will only respond to queries on the # system mib group until this file is replaced or modified for # security purposes. Examples are shown below about how to increase the # level of access. # By far, the most common question I get about the agent is "why won't # it work?", when really it should be "how do I configure the agent to # allow me to access it?" # # By default, the agent responds to the "public" community for read # only access, if run out of the box without any configuration file in # place. The following examples show you other ways of configuring # the agent so that you can change the community names, and give # yourself write access to the mib tree as well. # # For more information, read the FAQ as well as the snmpd.conf(5) # manual page. #### # First, map the community name "public" into a "security name" # sec.name source community com2sec notConfigUser default public #### # Second, map the security name into a group name: # groupName securityModel securityName group notConfigGroup v1 notConfigUser group notConfigGroup v2c notConfigUser #### # Third, create a view for us to let the group have rights to: # Make at least snmpwalk -v 1 localhost -c public system fast again. # name incl/excl subtree mask(optional) view systemview included .1 view systemview included .1.3.6.1.2.1.1 view systemview included .1.3.6.1.2.1.25.1.1 #### # Finally, grant the group read-only access to the systemview view. # group context sec.model sec.level prefix read write notif access notConfigGroup "" any noauth exact systemview none none # ----------------------------------------------------------------------------- # Here is a commented out example configuration that allows less # restrictive access. # YOU SHOULD CHANGE THE "COMMUNITY" TOKEN BELOW TO A NEW KEYWORD ONLY # KNOWN AT YOUR SITE. YOU *MUST* CHANGE THE NETWORK TOKEN BELOW TO # SOMETHING REFLECTING YOUR LOCAL NETWORK ADDRESS SPACE. ## sec.name source community #com2sec local localhost COMMUNITY #com2sec mynetwork NETWORK/24 COMMUNITY ## group.name sec.model sec.name #group MyRWGroup any local #group MyROGroup any mynetwork # #group MyRWGroup any otherv3user #... ## incl/excl subtree mask #view all included .1 80 ## -or just the mib2 tree- #view mib2 included .iso.org.dod.internet.mgmt.mib-2 fc ## context sec.model sec.level prefix read write notif #access MyROGroup "" any noauth 0 all none none #access MyRWGroup "" any noauth 0 all all all ############################################################################### # Sample configuration to make net-snmpd RFC 1213. # Unfortunately v1 and v2c don't allow any user based authentification, so # opening up the default config is not an option from a security point. # # WARNING: If you uncomment the following lines you allow write access to your # snmpd daemon from any source! To avoid this use different names for your # community or split out the write access to a different community and # restrict it to your local network. # Also remember to comment the syslocation and syscontact parameters later as # otherwise they are still read only (see FAQ for net-snmp). # # First, map the community name "public" into a "security name" # sec.name source community #com2sec notConfigUser default public # Second, map the security name into a group name: # groupName securityModel securityName #group notConfigGroup v1 notConfigUser #group notConfigGroup v2c notConfigUser # Third, create a view for us to let the group have rights to: # Open up the whole tree for ro, make the RFC 1213 required ones rw. # name incl/excl subtree mask(optional) #view roview included .1 #view rwview included system.sysContact #view rwview included system.sysName #view rwview included system.sysLocation #view rwview included interfaces.ifTable.ifEntry.ifAdminStatus #view rwview included at.atTable.atEntry.atPhysAddress #view rwview included at.atTable.atEntry.atNetAddress #view rwview included ip.ipForwarding #view rwview included ip.ipDefaultTTL #view rwview included ip.ipRouteTable.ipRouteEntry.ipRouteDest #view rwview included ip.ipRouteTable.ipRouteEntry.ipRouteIfIndex #view rwview included ip.ipRouteTable.ipRouteEntry.ipRouteMetric1 #view rwview included ip.ipRouteTable.ipRouteEntry.ipRouteMetric2 #view rwview included ip.ipRouteTable.ipRouteEntry.ipRouteMetric3 #view rwview included ip.ipRouteTable.ipRouteEntry.ipRouteMetric4 #view rwview included ip.ipRouteTable.ipRouteEntry.ipRouteType #view rwview included ip.ipRouteTable.ipRouteEntry.ipRouteAge #view rwview included ip.ipRouteTable.ipRouteEntry.ipRouteMask #view rwview included ip.ipRouteTable.ipRouteEntry.ipRouteMetric5 #view rwview included ip.ipNetToMediaTable.ipNetToMediaEntry.ipNetToMediaIfIndex #view rwview included ip.ipNetToMediaTable.ipNetToMediaEntry.ipNetToMediaPhysAddress #view rwview included ip.ipNetToMediaTable.ipNetToMediaEntry.ipNetToMediaNetAddress #view rwview included ip.ipNetToMediaTable.ipNetToMediaEntry.ipNetToMediaType #view rwview included tcp.tcpConnTable.tcpConnEntry.tcpConnState #view rwview included egp.egpNeighTable.egpNeighEntry.egpNeighEventTrigger #view rwview included snmp.snmpEnableAuthenTraps # Finally, grant the group read-only access to the systemview view. # group context sec.model sec.level prefix read write notif #access notConfigGroup "" any noauth exact roview rwview none ############################################################################### # System contact information # # It is also possible to set the sysContact and sysLocation system # variables through the snmpd.conf file: syslocation Unknown (edit /etc/snmp/snmpd.conf) syscontact Root <root@localhost> (configure /etc/snmp/snmp.local.conf) # Example output of snmpwalk: # % snmpwalk -v 1 localhost -c public system # system.sysDescr.0 = "SunOS name sun4c" # system.sysObjectID.0 = OID: enterprises.ucdavis.ucdSnmpAgent.sunos4 # system.sysUpTime.0 = Timeticks: (595637548) 68 days, 22:32:55 # system.sysContact.0 = "Me <me@somewhere.org>" # system.sysName.0 = "name" # system.sysLocation.0 = "Right here, right now." # system.sysServices.0 = 72 ############################################################################### # Logging # # We do not want annoying "Connection from UDP: " messages in syslog. # If the following option is commented out, snmpd will print each incoming # connection, which can be useful for debugging. dontLogTCPWrappersConnects yes # ----------------------------------------------------------------------------- ############################################################################### # Process checks. # # The following are examples of how to use the agent to check for # processes running on the host. The syntax looks something like: # # proc NAME [MAX=0] [MIN=0] # # NAME: the name of the process to check for. It must match # exactly (ie, http will not find httpd processes). # MAX: the maximum number allowed to be running. Defaults to 0. # MIN: the minimum number to be running. Defaults to 0. # # Examples (commented out by default): # # Make sure mountd is running proc mountd # Make sure there are no more than 4 ntalkds running, but 0 is ok too. proc ntalkd 4 # Make sure at least one sendmail, but less than or equal to 10 are running. proc sendmail 10 1 # A snmpwalk of the process mib tree would look something like this: # # % snmpwalk -v 1 localhost -c public .1.3.6.1.4.1.2021.2 # enterprises.ucdavis.procTable.prEntry.prIndex.1 = 1 # enterprises.ucdavis.procTable.prEntry.prIndex.2 = 2 # enterprises.ucdavis.procTable.prEntry.prIndex.3 = 3 # enterprises.ucdavis.procTable.prEntry.prNames.1 = "mountd" # enterprises.ucdavis.procTable.prEntry.prNames.2 = "ntalkd" # enterprises.ucdavis.procTable.prEntry.prNames.3 = "sendmail" # enterprises.ucdavis.procTable.prEntry.prMin.1 = 0 # enterprises.ucdavis.procTable.prEntry.prMin.2 = 0 # enterprises.ucdavis.procTable.prEntry.prMin.3 = 1 # enterprises.ucdavis.procTable.prEntry.prMax.1 = 0 # enterprises.ucdavis.procTable.prEntry.prMax.2 = 4 # enterprises.ucdavis.procTable.prEntry.prMax.3 = 10 # enterprises.ucdavis.procTable.prEntry.prCount.1 = 0 # enterprises.ucdavis.procTable.prEntry.prCount.2 = 0 # enterprises.ucdavis.procTable.prEntry.prCount.3 = 1 # enterprises.ucdavis.procTable.prEntry.prErrorFlag.1 = 1 # enterprises.ucdavis.procTable.prEntry.prErrorFlag.2 = 0 # enterprises.ucdavis.procTable.prEntry.prErrorFlag.3 = 0 # enterprises.ucdavis.procTable.prEntry.prErrMessage.1 = "No mountd process running." # enterprises.ucdavis.procTable.prEntry.prErrMessage.2 = "" # enterprises.ucdavis.procTable.prEntry.prErrMessage.3 = "" # enterprises.ucdavis.procTable.prEntry.prErrFix.1 = 0 # enterprises.ucdavis.procTable.prEntry.prErrFix.2 = 0 # enterprises.ucdavis.procTable.prEntry.prErrFix.3 = 0 # # Note that the errorFlag for mountd is set to 1 because one is not # running (in this case an rpc.mountd is, but thats not good enough), # and the ErrMessage tells you what's wrong. The configuration # imposed in the snmpd.conf file is also shown. # # Special Case: When the min and max numbers are both 0, it assumes # you want a max of infinity and a min of 1. # # ----------------------------------------------------------------------------- ############################################################################### # Executables/scripts # # # You can also have programs run by the agent that return a single # line of output and an exit code. Here are two examples. # # exec NAME PROGRAM [ARGS ...] # # NAME: A generic name. The name must be unique for each exec statement. # PROGRAM: The program to run. Include the path! # ARGS: optional arguments to be passed to the program # a simple hello world exec echotest /bin/echo hello world # Run a shell script containing: # # #!/bin/sh # echo hello world # echo hi there # exit 35 # # Note: this has been specifically commented out to prevent # accidental security holes due to someone else on your system writing # a /tmp/shtest before you do. Uncomment to use it. # #exec shelltest /bin/sh /tmp/shtest # Then, # % snmpwalk -v 1 localhost -c public .1.3.6.1.4.1.2021.8 # enterprises.ucdavis.extTable.extEntry.extIndex.1 = 1 # enterprises.ucdavis.extTable.extEntry.extIndex.2 = 2 # enterprises.ucdavis.extTable.extEntry.extNames.1 = "echotest" # enterprises.ucdavis.extTable.extEntry.extNames.2 = "shelltest" # enterprises.ucdavis.extTable.extEntry.extCommand.1 = "/bin/echo hello world" # enterprises.ucdavis.extTable.extEntry.extCommand.2 = "/bin/sh /tmp/shtest" # enterprises.ucdavis.extTable.extEntry.extResult.1 = 0 # enterprises.ucdavis.extTable.extEntry.extResult.2 = 35 # enterprises.ucdavis.extTable.extEntry.extOutput.1 = "hello world." # enterprises.ucdavis.extTable.extEntry.extOutput.2 = "hello world." # enterprises.ucdavis.extTable.extEntry.extErrFix.1 = 0 # enterprises.ucdavis.extTable.extEntry.extErrFix.2 = 0 # Note that the second line of the /tmp/shtest shell script is cut # off. Also note that the exit status of 35 was returned. # ----------------------------------------------------------------------------- ############################################################################### # disk checks # # The agent can check the amount of available disk space, and make # sure it is above a set limit. # disk PATH [MIN=100000] # # PATH: mount path to the disk in question. # MIN: Disks with space below this value will have the Mib's errorFlag set. # Default value = 100000. # Check the / partition and make sure it contains at least 10 megs. disk / 10000 # % snmpwalk -v 1 localhost -c public .1.3.6.1.4.1.2021.9 # enterprises.ucdavis.diskTable.dskEntry.diskIndex.1 = 0 # enterprises.ucdavis.diskTable.dskEntry.diskPath.1 = "/" Hex: 2F # enterprises.ucdavis.diskTable.dskEntry.diskDevice.1 = "/dev/dsk/c201d6s0" # enterprises.ucdavis.diskTable.dskEntry.diskMinimum.1 = 10000 # enterprises.ucdavis.diskTable.dskEntry.diskTotal.1 = 837130 # enterprises.ucdavis.diskTable.dskEntry.diskAvail.1 = 316325 # enterprises.ucdavis.diskTable.dskEntry.diskUsed.1 = 437092 # enterprises.ucdavis.diskTable.dskEntry.diskPercent.1 = 58 # enterprises.ucdavis.diskTable.dskEntry.diskErrorFlag.1 = 0 # enterprises.ucdavis.diskTable.dskEntry.diskErrorMsg.1 = "" # ----------------------------------------------------------------------------- ############################################################################### # load average checks # # load [1MAX=12.0] [5MAX=12.0] [15MAX=12.0] # # 1MAX: If the 1 minute load average is above this limit at query # time, the errorFlag will be set. # 5MAX: Similar, but for 5 min average. # 15MAX: Similar, but for 15 min average. # Check for loads: load 12 14 14 # % snmpwalk -v 1 localhost -c public .1.3.6.1.4.1.2021.10 # enterprises.ucdavis.loadTable.laEntry.loadaveIndex.1 = 1 # enterprises.ucdavis.loadTable.laEntry.loadaveIndex.2 = 2 # enterprises.ucdavis.loadTable.laEntry.loadaveIndex.3 = 3 # enterprises.ucdavis.loadTable.laEntry.loadaveNames.1 = "Load-1" # enterprises.ucdavis.loadTable.laEntry.loadaveNames.2 = "Load-5" # enterprises.ucdavis.loadTable.laEntry.loadaveNames.3 = "Load-15" # enterprises.ucdavis.loadTable.laEntry.loadaveLoad.1 = "0.49" Hex: 30 2E 34 39 # enterprises.ucdavis.loadTable.laEntry.loadaveLoad.2 = "0.31" Hex: 30 2E 33 31 # enterprises.ucdavis.loadTable.laEntry.loadaveLoad.3 = "0.26" Hex: 30 2E 32 36 # enterprises.ucdavis.loadTable.laEntry.loadaveConfig.1 = "12.00" # enterprises.ucdavis.loadTable.laEntry.loadaveConfig.2 = "14.00" # enterprises.ucdavis.loadTable.laEntry.loadaveConfig.3 = "14.00" # enterprises.ucdavis.loadTable.laEntry.loadaveErrorFlag.1 = 0 # enterprises.ucdavis.loadTable.laEntry.loadaveErrorFlag.2 = 0 # enterprises.ucdavis.loadTable.laEntry.loadaveErrorFlag.3 = 0 # enterprises.ucdavis.loadTable.laEntry.loadaveErrMessage.1 = "" # enterprises.ucdavis.loadTable.laEntry.loadaveErrMessage.2 = "" # enterprises.ucdavis.loadTable.laEntry.loadaveErrMessage.3 = "" # ----------------------------------------------------------------------------- ############################################################################### # Extensible sections. # # This alleviates the multiple line output problem found in the # previous executable mib by placing each mib in its own mib table: # Run a shell script containing: # # #!/bin/sh # echo hello world # echo hi there # exit 35 # # Note: this has been specifically commented out to prevent # accidental security holes due to someone else on your system writing # a /tmp/shtest before you do. Uncomment to use it. # # exec .1.3.6.1.4.1.2021.50 shelltest /bin/sh /tmp/shtest # % snmpwalk -v 1 localhost -c public .1.3.6.1.4.1.2021.50 # enterprises.ucdavis.50.1.1 = 1 # enterprises.ucdavis.50.2.1 = "shelltest" # enterprises.ucdavis.50.3.1 = "/bin/sh /tmp/shtest" # enterprises.ucdavis.50.100.1 = 35 # enterprises.ucdavis.50.101.1 = "hello world." # enterprises.ucdavis.50.101.2 = "hi there." # enterprises.ucdavis.50.102.1 = 0 # Now the Output has grown to two lines, and we can see the 'hi # there.' output as the second line from our shell script. # # Note that you must alter the mib.txt file to be correct if you want # the .50.* outputs above to change to reasonable text descriptions. # Other ideas: # # exec .1.3.6.1.4.1.2021.51 ps /bin/ps # exec .1.3.6.1.4.1.2021.52 top /usr/local/bin/top # exec .1.3.6.1.4.1.2021.53 mailq /usr/bin/mailq # ----------------------------------------------------------------------------- ############################################################################### # Pass through control. # # Usage: # pass MIBOID EXEC-COMMAND # # This will pass total control of the mib underneath the MIBOID # portion of the mib to the EXEC-COMMAND. # # Note: You'll have to change the path of the passtest script to your # source directory or install it in the given location. # # Example: (see the script for details) # (commented out here since it requires that you place the # script in the right location. (its not installed by default)) # pass .1.3.6.1.4.1.2021.255 /bin/sh /usr/local/local/passtest # % snmpwalk -v 1 localhost -c public .1.3.6.1.4.1.2021.255 # enterprises.ucdavis.255.1 = "life the universe and everything" # enterprises.ucdavis.255.2.1 = 42 # enterprises.ucdavis.255.2.2 = OID: 42.42.42 # enterprises.ucdavis.255.3 = Timeticks: (363136200) 42 days, 0:42:42 # enterprises.ucdavis.255.4 = IpAddress: 127.0.0.1 # enterprises.ucdavis.255.5 = 42 # enterprises.ucdavis.255.6 = Gauge: 42 # # % snmpget -v 1 localhost public .1.3.6.1.4.1.2021.255.5 # enterprises.ucdavis.255.5 = 42 # # % snmpset -v 1 localhost public .1.3.6.1.4.1.2021.255.1 s "New string" # enterprises.ucdavis.255.1 = "New string" # # For specific usage information, see the man/snmpd.conf.5 manual page # as well as the local/passtest script used in the above example. ############################################################################### # Further Information # # See the snmpd.conf manual page, and the output of "snmpd -H".

pgjdbc数据库的ssl证书验证源码有几点不懂的地方

postgresql 数据库用证书验证,看了一下源码,但是ssl证书验证有几点不懂的地方. 下面是pgjdbc获取完数据库的连接后, 开始启用ssl证书验证的流程. 我的问题: 过程我都看明白了, 但是不知道为什么它要这么做, 还是说这是个标准, 有人可以帮我讲解一下,或者给点资料参考也行, 谢谢 为了保持代码的简洁性,代码有删减. ``` private PGStream enableSSL(PGStream pgStream, SslMode sslMode, Properties info, int connectTimeout) throws IOException, PSQLException { // 发送SSL请求包 pgStream.sendInteger4(8);//发送一个4字节的整数到后端。 pgStream.sendInteger2(1234);//发送一个2字节整数(短)到后端。 pgStream.sendInteger2(5679); pgStream.flush();//将任何挂起的输出刷新到后端。 // Now get the response from the backend, one of N, E, S. 现在从后端(N, E, S)中获取响应。 int beresp = pgStream.receiveChar();//从后端接收单个字符。 switch (beresp) { case 'S': // ssl 服务器支持ssl **org.herodbsql.ssl.MakeSSL.convert(pgStream, info);** return pgStream; } } ``` 上面可以看到,jdbc给数据库发了几个字节的整数, 然后获取响应,走不同的switch,但是不知道为什么这么做,接着进去看,convert方法 ``` public static void convert(PGStream stream, Properties info) throws PSQLException, IOException { LOGGER.log(Level.FINE, "converting regular socket connection to ssl"); **SSLSocketFactory factory = SocketFactoryFactory.getSslSocketFactory(info);** SSLSocket newConnection; // 将常规套接字连接转换为ssl newConnection = (SSLSocket) factory.createSocket(stream.getSocket(), stream.getHostSpec().getHost(), stream.getHostSpec().getPort(), true); // 我们必须手动调用，否则将隐藏异常 newConnection.setUseClientMode(true);// 设置使用客户端模式 newConnection.startHandshake();// 开始握手 stream.changeSocket(newConnection); } ``` 在看SocketFactoryFactory.getSslSocketFactory(info); ``` public static SSLSocketFactory getSslSocketFactory(Properties info) throws PSQLException {//获取Ssl套接字工厂 String classname = PGProperty.SSL_FACTORY.get(info);// 获取要使用的SSL工厂的类名 if (classname == null || "org.herodbsql.ssl.jdbc4.LibPQFactory".equals(classname) || "org.herodbsql.ssl.LibPQFactory".equals(classname)) { return new LibPQFactory(info); } } ``` 接着看 new LibPQFactory(info); 这个方法应该就是加载证书的地方 ``` public LibPQFactory(Properties info) throws PSQLException { try { SSLContext ctx = SSLContext.getInstance("TLS"); // or "SSL" ? // 确定默认文件位置 String pathsep = System.getProperty("file.separator");// 获取windows或者linux的文件夹分隔符 String defaultdir; boolean defaultfile = false; if (System.getProperty("os.name").toLowerCase().contains("windows")) { // It is Windows defaultdir = System.getenv("APPDATA") + pathsep + "herodbsql" + pathsep; // 获取指定环境变量的值。环境变量是一个依赖于系统的外部命名值。 } else { defaultdir = System.getProperty("user.home") + pathsep + ".herodbsql" + pathsep; } // Load the client's certificate and key 加载客户机的证书和密钥 String sslcertfile = PGProperty.SSL_CERT.get(info); if (sslcertfile == null) { // Fall back to default 退回到默认状态 defaultfile = true; sslcertfile = defaultdir + "herodbsql.crt"; } String sslkeyfile = PGProperty.SSL_KEY.get(info); if (sslkeyfile == null) { // Fall back to default defaultfile = true; sslkeyfile = defaultdir + "herodbsql.pk8"; } // Determine the callback handler 确定回调处理程序 CallbackHandler cbh; String sslpasswordcallback = PGProperty.SSL_PASSWORD_CALLBACK.get(info); if (sslpasswordcallback != null) { try { cbh = (CallbackHandler) ObjectFactory.instantiate(sslpasswordcallback, info, false, null); } catch (Exception e) { throw new PSQLException( GT.tr("The password callback class provided {0} could not be instantiated.", sslpasswordcallback), PSQLState.CONNECTION_FAILURE, e); } } else { cbh = new ConsoleCallbackHandler(PGProperty.SSL_PASSWORD.get(info));// 获取 sslkey的加密密码 } // If the properties are empty, give null to prevent client key selection 如果属性为空，则为null，以防止选择客户机密钥 km = new LazyKeyManager(("".equals(sslcertfile) ? null : sslcertfile), ("".equals(sslkeyfile) ? null : sslkeyfile), cbh, defaultfile);//创建lazykeymanagerduixinag TrustManager[] tm; SslMode sslMode = SslMode.of(info); if (!sslMode.verifyCertificate()) { // server validation is not required 不需要服务器验证 tm = new TrustManager[]{new NonValidatingTM()}; } else { // Load the server certificate 加载服务器证书 TrustManagerFactory tmf = TrustManagerFactory.getInstance("PKIX");// 创建证书信任管理器工厂 KeyStore ks; try { ks = KeyStore.getInstance("jks");// 读取秘钥是所需要用到的工具类 } catch (KeyStoreException e) { // this should never happen throw new NoSuchAlgorithmException("jks KeyStore not available"); } String sslrootcertfile = PGProperty.SSL_ROOT_CERT.get(info);//获取根证书 if (sslrootcertfile == null) { // Fall back to default sslrootcertfile = defaultdir + "root.crt"; } FileInputStream fis; try { fis = new FileInputStream(sslrootcertfile); // 获取根证书ca的文件流 } catch (FileNotFoundException ex) { throw new PSQLException( GT.tr("Could not open SSL root certificate file {0}.", sslrootcertfile), PSQLState.CONNECTION_FAILURE, ex); } try { CertificateFactory cf = CertificateFactory.getInstance("X.509");// // 获取X.509工厂实例 // Certificate[] certs = cf.generateCertificates(fis).toArray(new Certificate[]{}); //Does // not work in java 1.4 Object[] certs = cf.generateCertificates(fis).toArray(new Certificate[]{});//生成ca证书的数组视图 ks.load(null, null); for (int i = 0; i < certs.length; i++) { ks.setCertificateEntry("cert" + i, (Certificate) certs[i]);//设置证书条目 将给定的可信证书分配给给定的别名。 } tmf.init(ks); } catch (IOException ioex) { throw new PSQLException( GT.tr("Could not read SSL root certificate file {0}.", sslrootcertfile), PSQLState.CONNECTION_FAILURE, ioex); } catch (GeneralSecurityException gsex) { throw new PSQLException( GT.tr("Loading the SSL root certificate {0} into a TrustManager failed.", sslrootcertfile), PSQLState.CONNECTION_FAILURE, gsex); } finally { try { fis.close(); } catch (IOException e) { /* ignore */ } } tm = tmf.getTrustManagers(); } // finally we can initialize the context 最后，我们可以初始化上下文 try { ctx.init(new KeyManager[]{km}, tm, null); } catch (KeyManagementException ex) { throw new PSQLException(GT.tr("Could not initialize SSL context."), PSQLState.CONNECTION_FAILURE, ex); } factory = ctx.getSocketFactory(); } catch (NoSuchAlgorithmException ex) { throw new PSQLException(GT.tr("Could not find a java cryptographic algorithm: {0}.", ex.getMessage()), PSQLState.CONNECTION_FAILURE, ex); } } ```

java项目在本地上运行无问题，打war包到服务器上，部分功能有问题

tomcat日志： 23-Nov-2017 00:49:07.772 INFO [main] org.apache.catalina.core.StandardServer.await A valid shutdown command was received via the shutdown port. Stopping the Server instance. 23-Nov-2017 00:49:07.773 INFO [main] org.apache.coyote.AbstractProtocol.pause Pausing ProtocolHandler ["http-nio-8080"] 23-Nov-2017 00:49:07.824 INFO [main] org.apache.coyote.AbstractProtocol.pause Pausing ProtocolHandler ["ajp-nio-8009"] 23-Nov-2017 00:49:07.874 INFO [main] org.apache.catalina.core.StandardService.stopInternal Stopping service Catalina 23-Nov-2017 00:49:08.461 WARNING [localhost-startStop-2] org.apache.catalina.loader.WebappClassLoaderBase.clearReferencesJdbc The web application [MaintainSystem] registered the JDBC driver [com.mysql.jdbc.Driver] but failed to unregister it when the web application was stopped. To prevent a memory leak, the JDBC Driver has been forcibly unregistered. 23-Nov-2017 00:49:08.462 WARNING [localhost-startStop-2] org.apache.catalina.loader.WebappClassLoaderBase.clearReferencesThreads The web application [MaintainSystem] appears to have started a thread named [FileWatchdog] but has failed to stop it. This is very likely to create a memory leak. Stack trace of thread: java.lang.Thread.sleep(Native Method) org.apache.log4j.helpers.FileWatchdog.run(FileWatchdog.java:104) 23-Nov-2017 00:49:08.462 WARNING [localhost-startStop-2] org.apache.catalina.loader.WebappClassLoaderBase.clearReferencesThreads The web application [MaintainSystem] appears to have started a thread named [cluster-ClusterId{value='5a1593f852e92b26c5f5d86c', description='null'}-192.168.7.178:27017] but has failed to stop it. This is very likely to create a memory leak. Stack trace of thread: java.net.PlainSocketImpl.socketConnect(Native Method) java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350) java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206) java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188) java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392) java.net.Socket.connect(Socket.java:589) com.mongodb.connection.SocketStreamHelper.initialize(SocketStreamHelper.java:50) com.mongodb.connection.SocketStream.open(SocketStream.java:58) com.mongodb.connection.InternalStreamConnection.open(InternalStreamConnection.java:114) com.mongodb.connection.DefaultServerMonitor$ServerMonitorRunnable.run(DefaultServerMonitor.java:128) java.lang.Thread.run(Thread.java:745) 23-Nov-2017 00:49:08.463 WARNING [localhost-startStop-2] org.apache.catalina.loader.WebappClassLoaderBase.clearReferencesThreads The web application [MaintainSystem] appears to have started a thread named [Thread-5] but has failed to stop it. This is very likely to create a memory leak. 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632 ms 23-Nov-2017 00:49:21.658 INFO [main] org.apache.catalina.core.StandardService.startInternal Starting service Catalina 23-Nov-2017 00:49:21.658 INFO [main] org.apache.catalina.core.StandardEngine.startInternal Starting Servlet Engine: Apache Tomcat/8.0.20 23-Nov-2017 00:49:21.681 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployWAR Deploying web application archive /home/dabai/apache-tomcat-8.0.20/webapps/MaintainSystem.war 23-Nov-2017 00:50:06.881 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployWAR Deployment of web application archive /home/dabai/apache-tomcat-8.0.20/webapps/MaintainSystem.war has finished in 45,198 ms 23-Nov-2017 00:50:06.882 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory /home/dabai/apache-tomcat-8.0.20/webapps/examples 23-Nov-2017 00:50:07.077 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory /home/dabai/apache-tomcat-8.0.20/webapps/examples has finished in 195 ms 23-Nov-2017 00:50:07.078 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory /home/dabai/apache-tomcat-8.0.20/webapps/manager 23-Nov-2017 00:50:07.103 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory /home/dabai/apache-tomcat-8.0.20/webapps/manager has finished in 25 ms 23-Nov-2017 00:50:07.104 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deploying web application directory /home/dabai/apache-tomcat-8.0.20/webapps/host-manager 23-Nov-2017 00:50:07.132 INFO [localhost-startStop-1] org.apache.catalina.startup.HostConfig.deployDirectory Deployment of web application directory /home/dabai/apache-tomcat-8.0.20/webapps/host-manager has finished in 28 ms 23-Nov-2017 00:50:07.133 INFO [localhost-startStop-1] 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毕业5年，我问遍了身边的大佬，总结了他们的学习方法

我问了身边10个大佬，总结了他们的学习方法，原来成功都是有迹可循的。

程序员如何通过造轮子走向人生巅峰？

前言：你所做的事情，也许暂时看不到成果。但不要灰心，你不是没有成长，而是在扎根。 程序员圈经常流行的一句话：“不要重复造轮子”。在计算机领域，我们将封装好的组件、库，叫做轮子。因为它可以拿来直接用，直接塞进我们的项目中，就能实现对应的功能。 有些同学会问，人家都已经做好了，你再来重新弄一遍，有什么意义？这不是在浪费时间吗。 殊不知，造轮子是一种学习方式，能快速进步，造得好，是自己超强能力的表...

推荐10个堪称神器的学习网站

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这些软件太强了，Windows必装！尤其程序员！

Windows可谓是大多数人的生产力工具，集娱乐办公于一体，虽然在程序员这个群体中都说苹果是信仰，但是大部分不都是从Windows过来的，而且现在依然有很多的程序员用Windows。 所以，今天我就把我私藏的Windows必装的软件分享给大家，如果有一个你没有用过甚至没有听过，那你就赚了????，这可都是提升你幸福感的高效率生产力工具哦！ 走起！???? NO、1 ScreenToGif 屏幕，摄像头和白板...

阿里面试一个ArrayList我都能跟面试官扯半小时

我是真的没想到，面试官会这样问我ArrayList。

曾经优秀的人，怎么就突然不优秀了。

职场上有很多辛酸事，很多合伙人出局的故事，很多技术骨干被裁员的故事。说来模板都类似，曾经是名校毕业，曾经是优秀员工，曾经被领导表扬，曾经业绩突出，然而突然有一天，因为种种原因，被裁员了，...

大学四年因为知道了这32个网站，我成了别人眼中的大神！

依稀记得，毕业那天，我们导员发给我毕业证的时候对我说“你可是咱们系的风云人物啊”，哎呀，别提当时多开心啦????，嗯，我们导员是所有导员中最帅的一个，真的???? 不过，导员说的是实话，很多人都叫我大神的，为啥，因为我知道这32个网站啊，你说强不强????，这次是绝对的干货，看好啦，走起来！ PS：每个网站都是学计算机混互联网必须知道的，真的牛杯，我就不过多介绍了，大家自行探索，觉得没用的，尽管留言吐槽吧???? 社...

良心推荐，我珍藏的一些Chrome插件

上次搬家的时候，发了一个朋友圈，附带的照片中不小心暴露了自己的 Chrome 浏览器插件之多，于是就有小伙伴评论说分享一下我觉得还不错的浏览器插件。 我下面就把我日常工作和学习中经常用到的一些 Chrome 浏览器插件分享给大家，随便一个都能提高你的“生活品质”和工作效率。 Markdown Here Markdown Here 可以让你更愉快的写邮件，由于支持 Markdown 直接转电子邮...

看完这篇HTTP，跟面试官扯皮就没问题了

我是一名程序员，我的主要编程语言是 Java，我更是一名 Web 开发人员，所以我必须要了解 HTTP，所以本篇文章就来带你从 HTTP 入门到进阶，看完让你有一种恍然大悟、醍醐灌顶的感觉。 最初在有网络之前，我们的电脑都是单机的，单机系统是孤立的，我还记得 05 年前那会儿家里有个电脑，想打电脑游戏还得两个人在一个电脑上玩儿，及其不方便。我就想为什么家里人不让上网，我的同学 xxx 家里有网，每...

史上最全的IDEA快捷键总结

现在Idea成了主流开发工具，这篇博客对其使用的快捷键做了总结，希望对大家的开发工作有所帮助。

阿里程序员写了一个新手都写不出的低级bug，被骂惨了。

这种新手都不会范的错，居然被一个工作好几年的小伙子写出来，差点被当场开除了。

谁是华为扫地僧？

是的，华为也有扫地僧！2020年2月11-12日，“养在深闺人不知”的华为2012实验室扫地僧们，将在华为开发者大会2020（Cloud）上，和大家见面。到时，你可以和扫地僧们，吃一个洋...

Idea 中最常用的10款插件（提高开发效率），一定要学会使用！

学习使用一些插件，可以提高开发效率。对于我们开发人员很有帮助。这篇博客介绍了开发中使用的插件。

AI 没让人类失业，搞 AI 的人先失业了

最近和几个 AI 领域的大佬闲聊 根据他们讲的消息和段子 改编出下面这个故事 如有雷同 都是巧合 1. 老王创业失败，被限制高消费 “这里写我跑路的消息实在太夸张了。” 王葱葱哼笑一下，把消息分享给群里。 阿杰也看了消息，笑了笑。在座几位也都笑了。 王葱葱是个有名的人物，21岁那年以全额奖学金进入 KMU 攻读人工智能博士，累计发表论文 40 余篇，个人技术博客更是成为深度学习领域内风向标。 ...

2020年，冯唐49岁：我给20、30岁IT职场年轻人的建议

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最全最强！世界大学计算机专业排名总结！

我正在参与CSDN200进20，希望得到您的支持，扫码续投票5次。感谢您！ （为表示感谢，您投票后私信我，我把我总结的人工智能手推笔记和思维导图发送给您，感谢！） 目录 泰晤士高等教育世界大学排名 QS 世界大学排名 US News 世界大学排名 世界大学学术排名（Academic Ranking of World Universities） 泰晤士高等教育世界大学排名 中国共...

作为一名大学生，如何在B站上快乐的学习？

B站是个宝，谁用谁知道???? 作为一名大学生，你必须掌握的一项能力就是自学能力，很多看起来很牛X的人，你可以了解下，人家私底下一定是花大量的时间自学的，你可能会说，我也想学习啊，可是嘞，该学习啥嘞，不怕告诉你，互联网时代，最不缺的就是学习资源，最宝贵的是啥？ 你可能会说是时间，不，不是时间，而是你的注意力，懂了吧！ 那么，你说学习资源多，我咋不知道，那今天我就告诉你一个你必须知道的学习的地方，人称...

那些年，我们信了课本里的那些鬼话

教材永远都是有错误的，从小学到大学，我们不断的学习了很多错误知识。 斑羚飞渡 在我们学习的很多小学课文里，有很多是错误文章，或者说是假课文。像《斑羚飞渡》： 随着镰刀头羊的那声吼叫，整个斑羚群迅速分成两拨，老年斑羚为一拨，年轻斑羚为一拨。 就在这时，我看见，从那拨老斑羚里走出一只公斑羚来。公斑羚朝那拨年轻斑羚示意性地咩了一声，一只半大的斑羚应声走了出来。一老一少走到伤心崖，后退了几步，突...

一个程序在计算机中是如何运行的？超级干货！！！

强烈声明：本文很干，请自备茶水！???? 开门见山，咱不说废话！ 你有没有想过，你写的程序，是如何在计算机中运行的吗？比如我们搞Java的，肯定写过这段代码 public class HelloWorld { public static void main(String[] args) { System.out.println("Hello World!"); } ...

【蘑菇街技术部年会】程序员与女神共舞，鼻血再次没止住。（文末内推）

蘑菇街技术部的年会，别开生面，一样全是美女。

那个在阿里养猪的工程师，5年了……

简介： 在阿里，走过1825天，没有趴下，依旧斗志满满，被称为“五年陈”。他们会被授予一枚戒指，过程就叫做“授戒仪式”。今天，咱们听听阿里的那些“五年陈”们的故事。 下一个五年，猪圈见！ 我就是那个在养猪场里敲代码的工程师，一年多前我和20位工程师去了四川的猪场，出发前总架构师慷慨激昂的说：同学们，中国的养猪产业将因为我们而改变。但到了猪场，发现根本不是那么回事：要个WIFI，没有；...

为什么程序猿都不愿意去外包？

分享外包的组织架构，盈利模式，亲身经历，以及根据一些外包朋友的反馈，写了这篇文章 ，希望对正在找工作的老铁有所帮助

Java校招入职华为，半年后我跑路了

何来 我，一个双非本科弟弟，有幸在 19 届的秋招中得到前东家华为（以下简称 hw）的赏识，当时秋招签订就业协议，说是入了某 java bg，之后一系列组织架构调整原因等等让人无法理解的神操作，最终毕业前夕，被通知调往其他 bg 做嵌入式开发（纯 C 语言）。 由于已至于校招末尾，之前拿到的其他 offer 又无法再收回，一时感到无力回天，只得默默接受。 毕业后，直接入职开始了嵌入式苦旅，由于从未...