Packet loss/Jitter

[Olliedawg]

Hey all,

 

Earlier in the week a ticket was created in relation to phone lines having poor connection outbound. I have been monitoring over the last few days and we seem to be getting pretty serious packet loss/spikes.

 

(Ping to ISP) packet loss to our ISP, high ping spikes + jitter on random occasions.

 

 

(Ping to router) Also getting random ping spikes to our router, highest of which was 2000ms.

 

 

I have contacted ISP and they have tested the line, fine from there end.

 

Does this sound like symptoms of a network loop? If so what are the best practices to deal with / find the cuplrit?

 

We have a range of network switches across site, some being newer Mikrotiks, others being assortments of Netgear/HP Procurves (nearing 10 years of age).

 

EDIT : seems to have stabilized a little after around 10 minutes.

 

Edited February 8, 2023 by Olliedawg

[psydii]

This is the third thing I've seen this morning that might be attributable to problems on the wider internet. Who is your ISP?

[Olliedawg]

We're on a leased line through Opus. They have reported no issues though.

 

That's what is making me think it may be a network loop, as i'm sure that some of our older switches do not have STP enabled, or even have the feature at all.

[Olliedawg]

Think i've narrowed this down to one of our IT rooms. All 3 IT rooms were in use this morning during form time, as soon as students began logging in, network went crazy.

 

Packet loss all over the place & ping spikes up to 200ms.

 

Going to have a real good look at all 3 of these rooms, as well as the switches for these rooms.

[Olliedawg]

SO for anyone still interested, I managed to isolate the issue to a cab in one of our IT rooms. It was indeed a network loop. The cable management (or lack of) in this specific cab was an absolute state, to the point you could barely see the switches. (large cab with 3 48 port switches.). I wish I had taken a photo of this to show you all, it would make you cringe!

 

Decided to just strip all cabling out of the cab & start again. Now this is the first time I have actually done this myself, and I don't think i've done a bad job .

 

On the plus side, I have been monitoring network traffic all this morning - NO Packet loss, no jitter .