Weird issue with Brocade switch appears to be throttling ports

[Nerdface Killah]

We have a Brocade GS648P switch which has 3 vlans on it. One being a generic vlan, the second is "management" but should be actually data and then there is a third which is our voice. There are certain ports that are trunked and in vlans 2 and 3 (voice/data). If you plug a computer into the pass through port of a voip phone you see upload speeds of 50-100Mbps. If you plug a computer directly into a switch port which is only on vlan 2 (data) you see 10/10 pretty much consistently. The main issue is that we have a Synology nas that we want to be backed up to Amazon S3 and when plugged directly into a vlan 2 switch port it takes a really long time.

I've swapped out the router with a basic DD-WRT router and it still happened. The router is a SonicWALL TZ100 with no services running at all. We have a ESXi host with three guests, one Exchange, one AD DC, DNS, DHCP and a file server.

I've looked high and low into the Brocade for qos, port throttling, acl rate limiting etc. but literally nothing is set except for all ports are trust dscp enabled. I have tried disabling it on a single port but it didn't do much.

Any ideas why a computer connected to the pass through port of a phone would allow it to utilize our full connection speed? We have fiber to the building. Thank you in advance!

 

[diizzy]

Have you checked link speed?
Have you tried swapping cables?
Do you have the latest firmware installed?
Have you looked at the rsync (or whatever you use) and tcp settings on the Synology? Different protocols will have differently performance characteristics depending on window size and latency.
//Danne

 

[Nerdface Killah]

Have you checked link speed?
Have you tried swapping cables?
Do you have the latest firmware installed?
Have you look at the rsync (or whatever you use) and tcp settings on the Synology? Different protocols will have differently performance characteristics depending on window size and latency.
//Danne

Looked at link speed, tried different options, 10, 100, 1000, auto, etc. No change.

Will check about firmware.

Last but not least the Synology when connected to a phone uploads quite fast, we're talking 5-10MBps easily. Although I did play with link speed and tcp settings as well.

 

[diizzy]

For how long have you observed this difference in speed?
Just making sure that you aren't looking at some speed burst for the first minute or so.
//Danne