Note
This procedure only applies to VSP 4900 Series, VSP 7400 Series, and XA1400 Series.
Adjust the TCP maximum segment size (MSS) to improve the throughput for the TCP session over a Fabric Extend (FE) adjacency.
Note
If you downgrade to an earlier release that does not support this feature, you must disable the feature and save the configuration. Downgrading to an earlier release requires a compatible configuration file.
The default varies depending on hardware platform:
For XA1400 Series, this functionality is enabled when at least one Fabric Extend (FE) tunnel with a MTU less than or equal to 1500 is configured, and the value is auto-derived.
For VSP 4900 Series and VSP 7400 Series, this functionality is disabled. The default value, when enabled, is 1300.
enable
configure terminal
ip tcp adjust-mss <max-segment-size> [enable]
no ip tcp adjust-mss enable
Note
An auto-derived value is only supported on XA1400 Series.
no ip tcp adjust-mss enable
show ip tcp adjust-mss
Configure an MSS value of 1100 and verify the configuration.
Switch:1>enable Switch:1#configure terminal Enter configuration commands, one per line. End with CNTL/Z. Switch:1(config)#ip tcp adjust-mss 1200
Switch:1>show ip tcp adjust-mss ================================================================================ IP TCP Adjust MSS ================================================================================ ENABLE STATUS TCP MSS TCP MSS TYPE VALUE -------------------------------------------------------------------------------- TRUE ACTIVE MANUAL-CONFIG 1200
Disable the configured MSS adjustment value on XA1400 Series and verify the configuration:
.Switch:1>enable Switch:1#configure terminal Enter configuration commands, one per line. End with CNTL/Z. Switch:1(config)#no ip tcp adjust-mss enable Switch:1(config)#show ip tcp adjust-mss ============================================================================ IP TCP Adjust MSS ============================================================================ ENABLE STATUS TCP MSS TCP MSS TYPE VALUE ---------------------------------------------------------------------------- TRUE ACTIVE AUTO-DERIVED 1300