QoS on BigIp v4.2

Hi,

 

I have an older BigIP v4.2 and use it primarily to balance a few webservers (80/443) round robin. On one of the webservers, I need to run an ftp server primarily for people to download files. However, when people download from the ftp, the slowdown is noticeable on the website. Right now I am throttling the bandwidth from the ftp server, but I figure there has to be a more efficient way since a lot of the time the webserver is not busy at all and the ftp server could be using a lot more bandwidth...

 

I was wondering if it is possible to setup the BigIP to limit the bandwidth on the ftp server when traffic is coming in for the website (80/443). I have a virtual server already created for the ftp server which has a pool containing the internal ip of the ftp server. Connecting to it works fine, I just am curious if I can stall or limit the ftp traffic when there are requests coming in for the web site. I guess my first question is if my BIgIP can help me with this problem. I notice there are some fields called 'Link QoS; and 'IP ToS' for the pool, however I cant find much documentation on the web if these would be useful to me. From my reading it seems they are just ways to tag packets and don't really do any QoS of their own. I also have a tab in Filters for doing rate filtering. Would that be the right area to solve this problem?

 

 

Any help would be greatly appreciated! Thank you in advance!