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Forum Discussion

DennyK_144735's avatar
DennyK_144735
Icon for Nimbostratus rankNimbostratus
Feb 20, 2014

BigIP LTM port translation - port selection process

Hey folks,   We have a load-balanced FTP server system that formerly resided behind an F5 3400 running BigIP LTM 10.0.1. We have recently moved it to a new F5, a 3900 running version 10.2.4. On bo...
active ftp
application delivery
LTM
management
port translation
nitass's avatar
nitass
Icon for Employee rankEmployee
Feb 23, 2014

On the 3400/10.0.1 system, the ports being assigned when port translation was in effect were assigned sequentially (sometimes skipping a few numbers here and there, but always incrementing in sequence). However, on the new 3900/10.2.4 system, the ports being assigned for translation appear to be completely random.

 

i guess it is because 3400 does not support cmp but 3900. not sure if disabling cmp is a good idea, it may have some workaround for this.

 

sol7751: Overview of Clustered Multiprocessing (9.x - 10.x)

 

http://support.f5.com/kb/en-us/solutions/public/7000/700/sol7751.html

 

DennyK_144735's avatar
DennyK_144735
Icon for Nimbostratus rankNimbostratus
Feb 27, 2014
Thanks for the reply; not a bad notion, but unfortunately it doesn't look like that's the cause here. We tried disabling CMP for the VIP that our client is using, but the ports being assigned during port translation are still completely random and still occasionally repeat too quickly, causing the same issue.