darwinperez_kyn
Jun 07, 2024Nimbostratus
Insert host name in TCP data
Hello,
We have a scenario where a Mainframe is sending a transactional data(tcp) to F5 that needs to have a host name inserted to it. The problem is that, even irule or local policy is not making it work.
VS is set to standard.
I have a sample pcap below, and it shows that F5 with or without irule/policy, is not forwarding the traffic to the pool members--
Below is the sample irule --
when CLIENT_ACCEPTED {
TCP::collect 32
}
when CLIENT_DATA {
[TCP::payload 32] insert "Host" "xxxx.yyyy.zzzz"
TCP::release
}
Sample Policy --
Conditions
TCP address matches 'mainframe_ip_add' at client accepted time.
Actions
Insert HTTP Header named 'Host' with value 'xxxx.yyyy.zzzz' at request time.
My questions are-
- How F5 is handling the TCP Payload, is it possible to insert a hostname on a tcp data?
- Is there any other way to get this host name inserted?
- Why F5 is not doing a tcp 3-way handshake to the backend servers?
Will appreciate any help!
Thank you.
Darwin