Symptoms
- Migration fails with the following error:
PLESK_ERROR: Panel Migrator failed to start RPC Agent on ‘203.0.113.2’ server.
RPC Agent is required for communication between current server and ‘203.0.113.2’ server
PLESK_ERROR: Failed to fetch basic information about resellers, clients and domains data from source serversÂ
Cause: unpack requires a string argument of length 4Â
That is a critical error, migration was stopped. -
RPC Agent
is installed and running on the source server. - It is not possible to connect from target server to source one via
telnet
utility:C:> telnet <source_server_IP> 10155
Note: if
telnet
utility is not installed check the article Install Telnet Client -
On target server Â
%plesk_dir%varmodulespanel-migratorsessionsTIME_STAMPdebug.log
  has the following error:PleskConnectionCheckError: Failed to connect to target Plesk server by Plesk API: <urlopen error [Errno 10054] An existing connection was forcibly closed by the remote host>
Cause
Network issue, required port for migration is closed by a firewall.
Resolution
Check network and make sure that is it possible to connect from target server to source one on port 10155.
Additional Information
Migration cannot be started: Panel Migrator failed to install RPC Agent