Mar 27, 2026 - For details about updated CVE-2025-53521 (BIG-IP APM vulnerability), refer to K000156741.

Forum Discussion

sand87ch's avatar
sand87ch
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Nov 03, 2022

send command in HTTP_REQUEST_DATA is it async

I have been searching the docs for this but couldnt find a satisfactory answer.We are mirroring the traffic from a bigip virtual server to a server of our own.in order to do some performanc etuning i...
cloud
Dario_Garrido's avatar
Dario_Garrido
Icon for Noctilucent rankNoctilucent
Nov 04, 2022

Hello sand87ch,

In order to get a better performance sending this mirroring traffic you could try to use HSL (High Speed Logging) to send those requests.

An example:

set mypayload "mypayload"
set hsl [HSL::open -proto TCP -pool $mypool]
HSL::send $hsl "POST /path/resource HTTP/1.0\nConnection: keep-alive\nHost: myserver\nContent-Type:text/plain;\nContent-Length:[string length $mypayload]\n\n$mypayload"

 

sand87ch's avatar
sand87ch
Icon for Cirrus rankCirrus
Nov 04, 2022

I am trying to mirror the request and response that passes via the Big Ip load balancer to the pool members to another virtual server in the BIGIP.The mirroring is configured via irules.I am using a sideband connection for the same.

Setup:-

1.Includes a F5 virtual server hosted on cloud

2.Another VIP(virtual server) entry created on the management portal,where this server doesnt actually exist.This VIP in turn is attached to a pool consisting of a server .

Data coming to bigip is intercepted using the inbuilt events for eg 

 

when HTTP_RESPONSE_DATA {
    set responseData [call respwithbody $requestId $debug $auth]
    set send_bytes [send -timeout $connectionTimeout -status send_status $conn_id $rsponseData]
    close $conn_id
    call printLog $debug " Sent bytes: $send_bytes"
}

 

where the conn_id is the connecteion to the above mentioned virual server(sideband connection to this server)

As per my reading on HSL

https://support.f5.com/csp/article/K50040950

it seems HSL would require changes vis a vis creating a publisher pool and it semes it doesnt log to the vip in my case.Correct me if i am wrong

With this scenarion is HSL is valid for me?