SBS 2011 - Internet Very Slow - Help Needed!

[GeneralGeek]

Hi all,
I recently installed an SBS 2011 Server for a client of mine, which had been working well for several weeks until around two weeks ago.

For reasons unknown the Internet speeds have dropped massively. I have reset and reconfigured the router, as well as plugging directly into the router to see if there is any issue there but it's working a full speed when a machine is hooked up to it directly.

Yesterday I moved the router, server and one machine to another switch and the Internet speed improved but was still not up to scratch. I also ran a cable directly to the switch from the server to try and rule out any bad cabling but that had no effect.

I have checked the Dell OpenManage software and there are no reports of any bad hardware or NICs, and the drivers appear to be the latest.

I am puzzled as to what the issue may be and my client is feeling the effects.

All ports are open on the router, and as I mentioned it was functioning well up until a short while ago. Oddly the SBS Console now refuses to email me a report but it can manually generate them. Not sure if that is a separate issue or linked?

The other thing I need to try next is to remove the AV (VSE 8.7i P5) to see if that helps.

Any advice is greatly welcomed.

[sameer22]

I think there is a kind of high latency from the nics. There are some tools on web which provides you information the latency of Nics. The bandwidth drop because number of reason. Issue is in the internet connection, policies which limit the bandwidth, poor cabling issue, mismatched router settings, etc. Also if someone downloads regularly the bandwidth is effected.

[GeneralGeek]

Many thanks for the reply, greatly appreciated.

I have so far performed the additional config changes:

Disable TCP Offload and RSS
Removed and updated the Virus protection to a version which doesn't use TDI drivers.
RAID Controller and NIC firmwares have been updated.

The download speeds over the Internet seem to be stable now but the upload is definitely the issue. It has improved for reasons unknown but it is losing half of it's speed whilst running through the system.

The next stage I will attempt is to properly remove all switches and recable it from scratch.

Currently the NICs are reporting good connectivity and the wiring diags I ran came back OK.

It's a frustrating situation as this system was running well, something has changed in the landscape to cause this.

As always - any helps is welcomed!