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kridsana's avatar
kridsana
Icon for Cirrocumulus rankCirrocumulus
Dec 26, 2012

How to clear Don't Fragment (DF) bit

there is some virtual server that have a problem that     packet segment lost when MTU = 1500     so i want to clear DF bit to fix this problem , and how to clear it?     than...
config
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nitass's avatar
nitass
Icon for Employee rankEmployee
Jan 09, 2013
additionally, mtu information in route metric is controlled by route.metrics.mtu db key. it will be created even pmtu is disabled. 

[root@B3900-R72-S18:Active:Standalone] config  tmsh list sys db one-line|grep mtu
sys db route.metrics.mtu { value "enable" }
sys db tm.enforcepathmtu { value "enable" }
sys db tm.minpathmtu { value "296" }
sys db tm.pathmtudiscovery { value "disable" }

[root@B3900-R72-S18:Active:Standalone] config  tmsh show net cmetric
Net::RouteMetric
Destination IP  HWaddress       TMM  rtt  rttvar  ssthresh  bandwidth  MTU
11.11.11.100    0:23:e9:0:65:4  1    0    0       0         0          1000
Destination IP  HWaddress       TMM  rtt  rttvar  ssthresh  bandwidth  MTU
11.11.11.100    0:23:e9:0:65:4  0    0    0       0         0          1000
Total records returned: 2