使用Jenkins 2.169
今天Jenkins服务器突然失败，并出现以下错误：
SEVERE: Failed Loading global config
java.io.IOException: Unable to read /somewhere/jenkins/home/config.xml
at hudson.XmlFile.unmarshal(XmlFile.java:181)
at hudson.XmlFile.unmarshal(XmlFile.java:161)
at jenkins.model.Jenkins.loadConfig(Jenkins.java:3043)
at jenkins.model.Jenkins.access$1300(Jenkins.java:309)
at jenkins.model.Jenkins$13.run(Jenkins.java:3145)
at org.jvnet.hudson.reactor.TaskGraphBuilder$TaskImpl.run(TaskGraphBuilder.java:169)
at org.jvnet.hudson.reactor.Reactor.runTask(Reactor.java:296)
at jenkins.model.Jenkins$5.runTask(Jenkins.java:1096)
at org.jvnet.hudson.reactor.Reactor$2.run(Reactor.java:214)
at org.jvnet.hudson.reactor.Reactor$Node.run(Reactor.java:117)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:748)
Caused by: jenkins.util.xstream.CriticalXStreamException: hudson.security.GlobalMatrixAuthorizationStrategy : hudson.security.GlobalMatrixAuthorizationStrategy
---- Debugging information ----
message : hudson.security.GlobalMatrixAuthorizationStrategy
cause-exception : com.thoughtworks.xstream.mapper.CannotResolveClassException
cause-message : hudson.security.GlobalMatrixAuthorizationStrategy
class : hudson.model.Hudson
required-type : hudson.model.Hudson
converter-type : hudson.util.RobustReflectionConverter
path : /hudson/authorizationStrategy
line number : 12
version : not available
-------------------------------
at hudson.util.RobustReflectionConverter.doUnmarshal(RobustReflectionConverter.java:354)
at hudson.util.RobustReflectionConverter.unmarshal(RobustReflectionConverter.java:268)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:72)
at com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:65)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:66)
at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:50)
at com.thoughtworks.xstream.core.TreeUnmarshaller.start(TreeUnmarshaller.java:134)
at com.thoughtworks.xstream.core.AbstractTreeMarshallingStrategy.unmarshal(AbstractTreeMarshallingStrategy.java:32)
at com.thoughtworks.xstream.XStream.unmarshal(XStream.java:1189)
at hudson.util.XStream2.unmarshal(XStream2.java:161)
at hudson.util.XStream2.unmarshal(XStream2.java:132)
at com.thoughtworks.xstream.XStream.unmarshal(XStream.java:1173)
at hudson.XmlFile.unmarshal(XmlFile.java:178)
... 12 more
Caused by: com.thoughtworks.xstream.mapper.CannotResolveClassException: hudson.security.GlobalMatrixAuthorizationStrategy
发现罪魁祸首是两个缺少的插件：
matrix-auth
ldap
我可以通过手动从另一台服务器复制插件来恢复Jenkins。复制的文件：
jenkins/home/plugins/matrix-auth
jenkins/home/plugins/matrix-auth.jpi
jenkins/home/plugins/ldap
jenkins/home/plugins/ldap.jpi
首先，我安装了matrix-auth。然后出现以下错误，表明ldap也存在问题：
Caused by: jenkins.util.xstream.CriticalXStreamException:
hudson.security.LDAPSecurityRealm : hudson.security.LDAPSecurityRealm
---- Debugging information ----
message : hudson.security.LDAPSecurityRealm
cause-exception :
com.thoughtworks.xstream.mapper.CannotResolveClassException
cause-message : hudson.security.LDAPSecurityRealm
class : hudson.model.Hudson
required-type : hudson.model.Hudson
converter-type : hudson.util.RobustReflectionConverter
path : /hudson/securityRealm
line number : 53
version : not available
-------------------------------
经过进一步调查，发现许多插件被删除了（另外，我发现了罪魁祸首，它与Jenkins无关）。因此，解决方案的一部分是从另一个Jenkins服务器复制整个插件目录。