[Scottish] Network testing tools?

[Daragh Mc Grath]

Mark Robinson wrote:

> Hello S.L.U.G,

Hey Mark,

> I'm having trouble proving to Demon that there are problems with an
> ADSL connection. It's _really_ slow at times, comes to a halt, then
> everything seems to load.  We've had pings with 19% packet loss to one
> of Demon's own name servers!

Being from Ireland, I'm not familiar with the set-up over there with how 
ISP's interact with telco's etc, however, have you been onto your ISP to 
have them check things out? Are they noticing anything on the line 
itself that may be causing the prob (high gain, Capacitance / voltage 
issues etc). Packet loss like this has a high probability of being line 
related more so than anything else.

> Does anyone have any recommendations for network testing tools to try
> and pin down the problem?  I tried doing a traceroute and then running
> pings to all hops along the route, but there's nothing consistent.

Traceroute and ping are the ultimate network diagnostic tools tbh, if, 
as you say, you are having 19% packet loss to a Demon NS, what does the 
trace to said NS show, is there any unusually high latency hops, or is 
there timeouts along the way anywhere? Are you consistently seeing 19% 
packet to said host?

Has this problem always been apparent, or has it only surfaced recently?

One other thing that you may want to check is your MTU settings on your 
router. Again, I'm not sure what they should be in your instance, I'm 
sure someone else on list may be able to provide you with the correct 
value's, but I've seen that cause a lot of problems with our customers 
over here, and is always worth checking.

> *sound of hair being removed by the handful*

Fear not...your solution will be found! :)

-- 
Regards,
Daragh
http://www.daraghmcg.org