Slow Internet Traffic on Vlans- Too Stupid to figure out

[bmcnally82]

I have an issue that has just cropped up on my network last week and have no idea why! And it doesn't help that I'm an idiot!!

In a nutshell, here's my problem...

Any device that is not a member of the primary vlan on the core is suffering from extremely slow Internet traffic, all other network traffic routes normal (ie: Exchange, Intranet, File Server, etc). Sometimes web pages load without issue, sometimes they don't. I can't seem to find the smoking gun. My core switch is a layer 3 HP Procurve 5406zl and my edge switches are Procurve 2848's. Each Edge has its own vlan that is routed on the core. I'm not talking a huge network here; just 2 vlans are having issues (vlan 7 and vlan5). Anyone on the primary vlan (network 192.168.4.0) does not suffer from this issue. My gateway is 192.168.4.1 and I'm able to perform trace routes out the edge switches to external websites. I'm not seeing anything out of place on the core, nor have there been any major network changes other than enabling RipV2 earlier in the week (all static routes were left in place). Any ideas on what could cause this type of issue all of a sudden? I'm starting to have users come to me justifying the reason why they need Internet to do their jobs... awkward.

Attached is the core 'show tech'. Any help would be greatly appreciated!!

[Matt Hobbs · Accepted solution]

Try removing the following lines, they should not be needed as the switch already knows these local routes.

ip route 192.168.5.0 255.255.255.0 vlan 5
ip route 192.168.6.0 255.255.255.0 vlan 6
ip route 192.168.7.0 255.255.255.0 vlan 7
ip route 192.168.201.0 255.255.255.0 vlan 201
ip route 192.168.202.0 255.255.255.0 vlan 202

And also update your firmware to at least K.12.57.

[bmcnally82]

Matt, thanks for the quick response! I updated to K.12.57, and removed the static routes per your suggestion.

This seemed promising...

Routing (PR_1000744325) â When a PC is using the switch as its default gateway, and that switch is set with a default route to another device on the same VLAN, duplication of packets may occur. Symptoms may include seeing TCP packets out of order due to retransmission.

I'll post my findings tomorrow! If I'm not hung first!!

[bmcnally82]

Matt... You the man!

Issue seemed to have disappeared after moving to K.12.57. Lost a bit of confidence in the 5406 on this one though...

Thanks again!

[bmcnally82]

Matt's suggestion worked... K.12.57 is the cure for slow vlan Internet traffic.