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Ismail_319212's avatar
Ismail_319212
Icon for Nimbostratus rankNimbostratus
Aug 04, 2017

Big ip LTM - MTU size

I have big IP LTM 2000 (12.1) , I have connected two web server to it, when ever I try to back up the data with the help of Symantec, I can backup only up to 25gb, sum times up to 10gb,after it shows...
application delivery
BIG-IP
devops
LTM
Hamish's avatar
Hamish
Icon for Cirrocumulus rankCirrocumulus
Aug 04, 2017

What makes you think it's the MTU? Do you have a tcpdump showing that path-mtu discovery is failing somewhere?

 

Generally when a bulk transfer like a backup fail for MTU, it's when the backup first starts streaming.

 

Note that MTU's MUST be the same across all hosts on a VLAN. (Yes, pedantic, and you can get away with odd hosts having different MTU's because most stacks will receive packages larger than their configured MTU. Right up until something strange goes wrong, so best to adhere to the specs)

 

H