Issue with CliMon (Remote Host Monitoring)

Products

• DX APM SaaS

Issue/Introduction

'Climon' is failing to fetch missing metrics.

Error messages:

 sshd[857544]: error: Received disconnect from <ip><port> com.jcraft.jsch.JSchException: Auth fail [preauth]
 sshd[857544]: Disconnected from authenticating user <user><ip><port>[preauth]

[ERROR] [IntroscopeAgent.CLIMon] [<ip>] Could not connect to remote service
[ERROR] [IntroscopeAgent.CLIMon] <ip>]
com.ca.apm.agent.extension.climon.exceptions.CliMonException: <ip>
       at com.ca.apm.agent.extension.climon.connectors.JSCHConnector.connect(JSCHConnector.java:61)
       at com.ca.apm.agent.extension.climon.connectors.CliConnectorService.connect(CliConnectorService.java:158)
       at com.ca.apm.agent.extension.climon.connectors.CliConnectorService.connectToService(CliConnectorService.java:115)
       at com.ca.apm.agent.extension.climon.commands.ConnectionAndAvailabilityCommand.execute(ConnectionAndAvailabilityCommand.java:36)
       at com.ca.apm.agent.extension.climon.CliMonChain.call(CliMonChain.java:66)
       at com.ca.apm.agent.extension.climon.CliMonChain.call(CliMonChain.java:38)
       at java.base/java.util.concurrent.FutureTask.run(Unknown Source)
       at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
       at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
       at java.base/java.lang.Thread.run(Unknown Source)
Caused by: com.jcraft.jsch.JSchException: Auth fail
       at com.jcraft.jsch.Session.connect(Session.java:519)
       at com.ca.apm.agent.extension.climon.connectors.JSCHConnector.startFreshConnection(JSCHConnector.java:99)
       at com.ca.apm.agent.extension.climon.connectors.JSCHConnector.connect(JSCHConnector.java:59)
       ... 9 common frames omitted

Resolution

The problem cropped up due to some changes made in Redhat latest release.

Had to apply SHA1 sub-policy to fix this. Check the vendor documentation on how to do this. User was running CentOS 7.

Additional Information

Other things tried :

• Commenting out the original PubkeyAcceptedAlgorithms line in the remote server /etc/ssh/sshd_config and replaced it with "PubkeyAcceptedAlgorithms +ssh-rsa".
• Reviewing public/private keys.