jumbo frames / SG 200-08 / not forwarding

[STUART KENDRICK]

Does anyone have jumbo frames running on this switch?

Using ICMP Echo as my test protocol, I can reach 1552 bytes in frame size ... but at 1553 and beyond (1578, 1932, 2090, 4138, 8978, 9014) , the switch swallows them.

When I physically swap out the SG 200-8 with an HP-1810 configured to support jumbo frames, those frame sizes above slide through just fine, and ICMP Echo Replies return just fine.

On the SG-200, I'm using Administration.., Port Management, Port Settings, {click on a port}, Edit... to modify MTU size.  I don't see any 'Enable Jumbo Frames' box that wants checking anywhere.

SG 200-08

Boot version 1.0.0.12

Firmware version 1.0.7.4

?

--sk

[V K Moorthy · Accepted solution]

Hi,

SG200-08 don't support Jumbo frames.Only SG200-24 and SG200-48 models will support jumbo frames.

Refer link below:(page no:5):

http://www.cisco.com/c/dam/en/us/td/docs/switches/lan/csbss/slm2024/administration/guide/SLM_Admin_Guide_Publish.pdf

regards

Moorthy

[Ashkaan42]

That document is not relevant to the OP's issue.  That document is referring to other SLM switches, not SG switches.  The SG-200-08 DOES support jumbo frames (hence the setting to change MTU to 9000+), however, there is a security feature blocking pings over 1500.  I don't know how to disable that setting.  In fact, if anyone knows that would be a huge help.

[efgslats84]

https://www.cisco.com/c/en/us/support/docs/smb/switches/cisco-small-business-200-series-managed-switches/smb2653-prevention-of-icmp-jumbo-frames-on-the-sg200-300-series-mana.html

Use the web configuration utility to configure jumbo frames, and choose Port management > Port Settings and choose Security > Denial of Service Prevention > Security Suite Settings to configure DoS prevention.

Maybe disabling the DdoS Prevention is a workaround?