Symptoms
Pressing 'Discover OS templates' button on some node gives:
Unable to get the templates list. Error: Invalid XML received from IM: <unspecified file>(175): invalid escape sequence.
The following is recorded to /var/log/poa.log:
Aug 13 03:15:06 osscore : ERR [UI:57c7d0fc:11438264:1471029304431 1:11952:b16f3b90 PACI ]: [ PACI::PACI_impl::parseJsonConf] PACI PTREE Exception: <unspecified file>(175): invalid escape sequence, json {"confs": [ { "ID": "82dd0a04-7a20-43c3-8ab8-a5b56a2c15bc", "EnvID": 1141562754, "Name": "CentOS6_x64"
Cause
Backslash '\' is used in the configuration of some VM OS template registered on the hardware node.
Resolution
Find the sport with backslash in the list of VM templates:
# prlctl list -t -i -j | egrep 'Name|\\'
Remove the backslash from whatever path revealed.