[OpenAFS] Re: RPC service unavailable, windows client, udebug works

Andrew Deason adeason@sinenomine.net
Wed, 5 Nov 2014 16:57:14 -0600

On Wed, 5 Nov 2014 10:43:12 -0600
Andrew Deason <adeason@sinenomine.net> wrote:

> Does syslog report the server coming back up later, if you don't try to
> access anything?

Well that was a stupid question. Somehow I momentarily forgot this was
on Windows. Oops.

On Wed, 05 Nov 2014 22:47:28 +0100
Christian <chanlists@googlemail.com> wrote:

> Sorry. Noticed that just after the email went out. rxdebug
> works just fine from the client. So now I am trying
> tcpdump -n host and host and udp
> both on the client or on the server. When I click on one of the
> directories which reside on volumes on, I get the "RPC..
> message " again, but I do not capture any traffic on the client. If I do
> a "fs checkservers" on the client, I capture on the client:

Well, you didn't see any traffic over port 7000, so that's still not
quite helpful yet. What may be happening is that the client has already
determined that the server was down, so it doesn't try to contact it. I
would imagine we would try to contact the server on an 'fs
checkservers', but maybe there is some detail of the Windows client I'm

Do you see packets go to port 7000 while running that 'rxdebug -version'
command? If you don't see those packets go across during that, you're
certainly not going to see any real traffic, and you'd need to figure
out that first.

You may try just looking at those IPs and not restricting to UDP, just
to see what traffic is going by. Or if there is too much TCP traffic,
try excluding TCP traffic instead of including UDP traffic. If IP
fragments are in play, you will see packets that will be identified as
neither UDP nor TCP (but you should still see at least _one_ packet
going to UDP port 7000, so that doesn't explain to me why you wouldn't
see any).

Or, you can try just capturing port 7000 UDP on the client side (not
restricted to any IP). You must see at least one packet going to port
7000 UDP at some point when the client is trying to access something. If
the client ever reports the fileserver coming back up, we must have sent
and received packets over port 7000 UDP.

Also, are you certain those are the only IPs that the client and server
have? If they also have other IPs assigned to them, the traffic could be
going over those. 

Andrew Deason