[Rack] UPS dropped off, sonic connection works better now

Dr. Jesus j at hug.gs
Sun Sep 19 00:45:56 UTC 2010

Miloh dropped off a Tripp-lite UPS (200 lbs, be careful) which is
charging underneath the EE bench closest to the server closet.  I
plugged my computer into its USB port and was able to read the battery
state.  I didn't do a load test.

The APC UPSes all say they want 24A peak and have L5-30 connectors.
Even if we change the plugs, we can't plug them into the 20A circuits.
 If the Tripp-lite works out and no one objects, I'm going to move the
APCs to the FSF GCC compile farm since they need it for some of their
weirder embedded hardware that doesn't come up right after a reset.

I also enabled state tracking in pf on both routers to make it easy to
see who's torrenting and hosing the link:

  # pfctl -s Sources ( states 1, connections 1, rate 0.0/0s ) ( states 3, connections 3, rate 0.0/0s ) ( states 1, connections 1, rate 0.0/0s ) ( states 1, connections 0, rate 0.0/0s )
... etc

The torrenting nodes are the ones with high connection rates in the
rightmost field.

Because pf doesn't have a DLM to enable updating distributed counters,
source tracking is per router and not shared across the pfsync link.
It's still pretty easy to look at both routers at the same time, just
add this to your .ssh/config:

Host *
        ControlMaster auto
        ControlPath /home/whatever/.sshcontrolsockets/%r@%h:%p

Then do a ssh -fN root at & ssh -fN root at to set up
persistent SSH tunnels to be reused by future SSH sessions.

Then do ssh root at pfctl -s Sources & ssh root at
pfctl -s Sources to generate the source tracking report from both

You can use nmblookup -A, avahi-browse -tar, OUI lookups, etc to find
out more about the computer with the IP address causing the problem.

Between throttling back tor on pony and getting someone to stop
torrenting at the space, the link characteristics of the sonic.net
line have improved significantly:


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