[hobbit] MEMPHYS went nuts

[Xymon User in Richmond]

On Sat, December 19, 2009 23:47, Jaime Kikpole wrote:
> I've been setting up Xymon since I heard about it a couple of days
> ago.  So far, its fantastic.  Unfortunately, after a UPS malfunction
> that caused a whole room to restart, I have an inexplicable alarm.
> Take a look at this red alarm:
>
>  Memory              Used       Total  Percentage
>  Physical     4294964640M       4084M 4294967231%
>  Swap                  0M       4096M          0%
>
> This is from a FreeBSD 7.x box that has 8GB of physical RAM and 4GB of
> swap.  According to "top", the physical memory is still about 6.75GB
> free.
>
> I've restarted the daemon on the host in question as well as on
> Xymon's GUI/web server.  I've even tried a bin/bb 127.0.0.1 "drop
> HOSTNAME memory" just to see if it would help.
>
> I'm not even sure where to start on this.  It was working well for a
> day or so before going bad like this.  My best guess right now is some
> kind of "wrap-around" problem with an integer or something like that
> causing bad data in memory.
>
> Suggestions?
>

I have not touched BSD in about two years, so just a stab with a rusty
fork.  My gut feel is same as yours, integer wrap or memory mismap sort of
thing.

How is this  host maintained WRT kernel and ports?  Any chance the kernel
or related components have been updated since the last previous reboot
and/or since the Xymon build, and that this reboot loaded the changes?  If
you're using freebsd-upgrade, could you be in the stage 1 reboot after a
kernel update now, i.e. needing to do another "freebsd-update install" to
complete?  I'd look at that, and also at possibly rebuilding/installing
Xymon.