在config.xml配置文件中找到这段关于ldap认证的信息：

  <securityRealm class="hudson.security.LDAPSecurityRealm" plugin="ldap@1.20">
    <disableMailAddre***esolver>false</disableMailAddre***esolver>
    <configurations>
      <jenkins.security.plugins.ldap.LDAPConfiguration>
        <server>ldap://XXXXXX.com:389</server>
        <rootDN>dc=XXXXXX,dc=com</rootDN>
        <inhibitInferRootDN>false</inhibitInferRootDN>
        <userSearchBase></userSearchBase>
        <userSearch>uid={0}</userSearch>
        <groupMembershipStrategy class="jenkins.security.plugins.ldap.FromGroupSearchLDAPGroupMembershipStrategy">
          <filter>cn=jenkins</filter>
        </groupMembershipStrategy>
        <managerDN>uid=jarry,ou=People,dc=XXXXXX,dc=com</managerDN>
        <managerPasswordSecret>{AQAAABAAAAAQWfZrb7qoIjewuj3SK/z53/oRo86cW5wi/t07QeW/4mM=}</managerPasswordSecret>
        <displayNameAttributeName>uid</displayNameAttributeName>
        <mailAddressAttributeName>mail</mailAddressAttributeName>
        <ignoreIfUnavailable>false</ignoreIfUnavailable>
        <extraEnvVars class="linked-hash-map">
          <entry>
            <string></string>
            <string></string>
          </entry>
        </extraEnvVars>
      </jenkins.security.plugins.ldap.LDAPConfiguration>
    </configurations>
    <userIdStrategy class="jenkins.model.IdStrategy$CaseInsensitive"/>
    <groupIdStrategy class="jenkins.model.IdStrategy$CaseInsensitive"/>
    <disableRolePrefixing>true</disableRolePrefixing>
  </securityRealm>

上面的配置不当导致了无法通过ldap认证，而且导致jenkins也无法正常登陆了，可以把上面一段修改成以下样子：

   <securityRealm class="hudson.security.HudsonPrivateSecurityRealm">
     <disableSignup>false</disableSignup>
     <enableCaptcha>false</enableCaptcha>
   </securityRealm>