Re: [OT] Ping mystery

["Karl E. Jorgensen" <karl@jorgensen.org.uk>]

Hi

On Sat, Nov 02, 2013 at 01:09:31PM -0400, Brad Alexander wrote:
> I have sort of a weird one here. On my network, I have my firewall, which has 3
> interfaces. eth0 to the internal network, eth1 to the DMZ with a wireless
> access point hanging off of it, and eth2 out to the interwebs.
> 
> My workstation is on the internal network, and i have a Nokia N900 on the wifi.
> I saw in the backup reports that the Nokia failed to back up because of long
> ping times. So I pinged it, and while every ping came back, and the "time="
> looked normal, it was running at about 1/3 speed. I tried a combination of
> pings and found the following:
> 
> * Pings from my workstation to the Nokia by hostname are slow;
> * Pings from the firewall are normal;
> * Pings from the access point are normal;
> * Pings from the workstation by IP are normal.
> 
> Now, I thought it might be an issue on my dns. It wasn't. The DNS responds
> normally with 1msec query times.

Hm... I'd suggest to take DNS out of the equation by:

* Make sure all pings are done by IP address, rather than DNS Name

* Use the -n option on ping to avoid the reverse DNS lookup...

Hope this helps
-- 
Karl E. Jorgensen