For more information regarding the security incident at F5, the actions we are taking to address it, and our ongoing efforts to protect our customers, click here.

Forum Discussion

Greg_33923's avatar
Greg_33923
Icon for Nimbostratus rankNimbostratus
Jun 23, 2009

Slow File upload and download Speeds via F5 BigIP

BIG-IP 9.4.4 Build 94.0 Hotfix HF3     We have some F5 Load balancers that are load balancing apache webservers and the traffic at the moment is pretty lightweight. However, we have introd...
config
design
dan_19334's avatar
dan_19334
Icon for Nimbostratus rankNimbostratus
Jun 24, 2009
We have seen this, especially downloading large files across a VPN connection, where going through the LTM was noticeably slower than going directly to the server.

 

 

For our situation, one thing we noticed was that the MSS is negotiated between the LTM and client at (something like) 1380 and was negotiated to 1480 between the LTM and web server. With large files, this caused the LTM to have to fragment each packet and significantly slowed down the overall download speed.

 

 

We enabled the "Proxy Maximum Segment" TCP Option which helped so that it is the same MSS on both sides of the connection and prevents fragmented packets.

 

 

-Dan