Unable to rebuild jobs

I have a jenkins server which jenkins was upgraded from version 2.220 to 2.387.1, all plugins have been upgraded.

When I rebuilt jobs, it gave me these output:
Started by user abc
Running as SYSTEM
Building in workspace /var/lib/jenkins/workspace/DEF_GW_ENROLL_USER_PREPROD
[DEF_GW_ENROLL_USER_PREPROD] $ /bin/bash -x /tmp/jenkins81696621479514690.sh

  • export SSH_CONF=/var/lib/jenkins/.ssh/config/ssh_config_preprod-ue1
  • SSH_CONF=/var/lib/jenkins/.ssh/config/ssh_config_preprod-ue1
  • echo PREPROD
  • export targets=batch-host
  • targets=batch-host
  • for host in ‘$targets’
  • ssh -F /var/lib/jenkins/.ssh/config/ssh_config_preprod-ue1 batch-host ‘sudo python add_user_pastdated.py web.pre.domain.com abc1234 1 target.internal.domain.com false AUTHSERVER_V1R1 KPREHA_002 8 PST true’
    ssh_exchange_identification: Connection closed by remote host
    Build step ‘Execute shell’ marked build as failure
    [WS-CLEANUP] Deleting project workspace…[WS-CLEANUP] Skipped based on build state FAILURE
    Finished: FAILURE

I’ve tried to do a manual ssh, by copying the config file from /var/lib/jenkins/.ssh/config/ssh_config_preprod-ue1 to ~/.ssh/, and then run the ssh command, the connection was successfully made, I was able to enter the server.

The jenkins.log is empty, and the ssh plugins show no error message, so I have no clues at the moment.

What possibly could be the root cause?