[Cialug] Troubleshooting high latency/low speed

[Matthew Nuzum]

On Mon, Jul 26, 2010 at 4:46 PM, Matthew Nuzum <newz at bearfruit.org> wrote:

> Hello, I've got a server and accessing it is slow lately (about a week
> now). Sometimes just slow, other times intolerably slow.
>
> Ping does not indicate too much prob. Latency is about 70-80ms which is
> fine. However SSH, HTTP and even HTTPS over a non-standard port all make it
> clear there is a problem. Can you suggest how to troubleshoot this?
>

With your help and also the help of some in our irc chat room (#cialug on
freenode) - thanks arreyder! I loaded up wireshark and found some possible
problems.

I sent an email to the service provider and as it turns out, it helped them
pin-down a trouble-maker on their network that was sending out loads of
broadcast traffic.

They shut that server down and the problem went away, almost as if by magic.

The funny thing is that I only experienced this problem on one of the four
servers I have there. I loaded tcpdump on one of the others and while I
found some broadcast traffic it was nothing comparatively. (this one host
was generating 2.4Mb/s pretty constantly according to iftop)

Of the four servers, 3 are dells, one running debian/xen, the other two
Ubuntu 8.04, and the fourth one, the one with this prob, is a Super Micro
running Ubuntu 8.04 w/ a debian/xen kernel.

Oh well, glad it's fixed now.
-- 
Matthew Nuzum
newz2000 on freenode, skype, linkedin, identi.ca and twitter

"Never stop learning" –Robert Nuzum (My dad)
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://cialug.org/pipermail/cialug/attachments/20100729/26ae26cd/attachment.htm