ProCurve 1810G & Jumbo frames

[rirosen]

Hi,

I have enabled jumbo frames on a 1810G switch.

I use two Linux boxes both capable of jumbo frames and try to ping, using for ex.: ping -M do -s 4000 hostname

This gives me 100% packet loss.

It looks like the switch is dropping the larger framed packages, but how can I verify this?

According to the documentation a large frame drop counter is supposed to be incremented in the switch, but where can I find this counter?

Thanks,

Rickard

[molsen]

Hello Rickard,

On the V1810G you need to enable jumbo frames globally, that provides support for frames up to 9216 bytes. If you are using 802.1Q tagged frames, then you should subtract 4 bytes from that when setting your MTU on the Linux boxes.

The jumbo frame feature can be enabled under Switching->Jumbo Frames.

I am not sure which documentation you refer to when mentioning the large frame drop counter. It is not available in the Web Interface. Via SNMP you can access the RMON port counters, but there is not one specifying the Giant Frames dropped, only a general drop and an error counter.

Additionally, in P.1.16 we fixed a bug where the state of the Jumbo Frame setting was not always saved across reboots. You may want to update to the latest we have released to our website: http://h10144.www1.hp.com/customercare/support/software/summarypages/p-j1810-c.htm

Kind regards,

Michael Olsen