Date: Wed, 31 Jul 2024 07:43:05 -0600
Subject: Re: [sloan-25mlog 7330] Re: 2.5m obslog 20240730 (SJD 60522)
From: "Daniel Oravetz"
>> However, later on, we found that stopping/starting the communication
>> process creates a new problem which leads us to be unable to move the
>> telescope in MCP or via tcc. In interlock GUI, MCP and MCP_ok on all
>> three axes became red. even through we can take, give semaphore via MCP,
>> but could not move the telescope at all. "tcc axis init" initializes
>> axes, but brake comes back before a motion starts. We tried stop/start
>> the communication process on MCP, which generates mcp.heartbeat alerts.
>> At this point, we have no choice than restart MCP. The starting MCP went
>> smoothly, but all three axes was registered at zero degrees. We reset
>> axes positions with az(alt, rot) set_pos_deg command. Things back to
>> normal, we tested slews via MCP and tcc, they went fine.
>
> This one sounds like a bug in the MCP communications process.
> Unfortunately, there is now nothing much we can do about it unless Jose
> has some ideas.  I inadvertently became the MCP point of contact by
> running the 2019 upgrade project, not through any expertise with the
> system.
I'm not saying this was the problem last night, but we've seen this kind
of abnormal behavior when more than one instance of the MCP processes are
running on the MCP machine. The main reason I mention it here is because
the last time I experienced it was also after a server restart (or a 'cold
start' test). From an actor/STUI perspective, an 'mcp ping' still
responds, but when you try to do anything of substance with moving the
telescope things aren't copacetic. There's a note on the MCP Restart
Instructions page about checking the running processes before starting
anything new (and killing old processes as needed), but I don't know if
there's a 'server restart' document elsewhere with that info?
Speaking of which, can someone please point-out the "server restart"
instructions page? We used to have a 'cold start' instructions page, but I
can't seem to locate it either? Maybe those things have merged or have
become slightly renamed?
Thanks,
Dan