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Error when setting up replication Task


Jul 21, 2017
I was hoping someone can help here. I have two on prem TrueNAS-13.0-U6.1 servers.. I am trying to do a replication snap shot from main server to my newly built back up server. I configured the snapshot to run every day and have configured the replication task as a push over NetCat SSH. I am not using encryption and both servers are on the same network. Thanks to Constantin for trying to help me.

My Main server that will be pushing the data has 1 large pool and SMB shares to each folder on the drive. I do not have any data sets created on the pool other than the default ones (Jail, IO Cage) I tried pushing the whole pool and also tried just push a individual data set I created called "test" and each attempt resulted in the same error. I made sure I ran a snapshot task before running the replication task. Please advise what am I doing wrong?

[2024/02/07 19:55:51] INFO     [Thread-32] [zettarepl.paramiko.replication_task__task_1] Connected (version 2.0, client OpenSSH_8.8-hpn14v15)
[2024/02/07 19:55:51] INFO     [Thread-32] [zettarepl.paramiko.replication_task__task_1] Authentication (publickey) successful!
[2024/02/07 19:55:52] INFO     [replication_task__task_1] [zettarepl.replication.pre_retention] Pre-retention destroying snapshots: []
[2024/02/07 19:55:52] INFO     [replication_task__task_1] [zettarepl.replication.run] For replication task 'task_1': doing push from 'BIGASSRAID/test' to 'BIGASSZFS' of snapshot='auto-2024-02-07_19-55' incremental_base=None receive_resume_token=None encryption=False
[2024/02/07 19:55:52] INFO     [replication_task__task_1] [zettarepl.paramiko.replication_task__task_1.sftp] [chan 5] Opened sftp connection (server version 3)
[2024/02/07 19:55:52] INFO     [replication_task__task_1] [zettarepl.transport.ssh_netcat] Automatically chose connect address ''
[2024/02/07 19:55:52] ERROR    [replication_task__task_1] [zettarepl.replication.run] For task 'task_1' unhandled replication error SshNetcatExecException(ExecException(1, 'pool or dataset is busy\n'), ExecException(1, 'I/O error\n'))
Traceback (most recent call last):
  File "/usr/local/lib/python3.9/site-packages/zettarepl/replication/run.py", line 181, in run_replication_tasks
  File "/usr/local/lib/python3.9/site-packages/zettarepl/replication/stuck.py", line 18, in retry_stuck_replication
    return func()
  File "/usr/local/lib/python3.9/site-packages/zettarepl/replication/run.py", line 182, in <lambda>
    lambda: run_replication_task_part(replication_task, source_dataset, src_context, dst_context,
  File "/usr/local/lib/python3.9/site-packages/zettarepl/replication/run.py", line 279, in run_replication_task_part
    run_replication_steps(step_templates, observer)
  File "/usr/local/lib/python3.9/site-packages/zettarepl/replication/run.py", line 637, in run_replication_steps
    replicate_snapshots(step_template, incremental_base, snapshots, encryption, observer)
  File "/usr/local/lib/python3.9/site-packages/zettarepl/replication/run.py", line 720, in replicate_snapshots
    run_replication_step(step, observer)
  File "/usr/local/lib/python3.9/site-packages/zettarepl/replication/run.py", line 797, in run_replication_step
    ReplicationProcessRunner(process, monitor).run()
  File "/usr/local/lib/python3.9/site-packages/zettarepl/replication/process_runner.py", line 33, in run
    raise self.process_exception
  File "/usr/local/lib/python3.9/site-packages/zettarepl/replication/process_runner.py", line 37, in _wait_process
  File "/usr/local/lib/python3.9/site-packages/zettarepl/transport/ssh_netcat.py", line 203, in wait
    raise SshNetcatExecException(connect_exec_error, self.listen_exec_error) from None
zettarepl.transport.ssh_netcat.SshNetcatExecException: Passive side: pool or dataset is busy
Active side: I/O error


Jul 21, 2017
Screenshot 2024-02-10 104706.png


Jun 13, 2013
I tried to use TrueNAS replication over GUI without much success due to my snapshot naming scheme zettarepl.py doesn't support.
However, when I did experiment with it, I only used the "Transport" section to be "SSH" only ( not "SSH+NETCAT").
I suspect this is your issue.