F5 BIG-IP icon   F5 BIGIP – Send logs to custom syslog file



For debugging purposes (or to simply to organize logs as you prefer) it would be interesting to send certain syslog messages to a custom file instead of the default ones like /var/log/ltm or /var/log/apm

Desired goal

This example shows the way to send syslog messages starting with the string #DEBUG# to the file /var/log/customlog

(You can replace both string and Read more

F5 BIG-IP icon   F5 BIGIP – Bug when using datagroups in LTM policies



Datagroups can be used in LTM policies to, for example, filter connections based on the client IP address (at least in my BIG-IP v13.0.0)

This is possible by adding a condition like this:
F5 BIGIP - Bug when using datagroups in LTM policies 1

“TCP” – “address” – “matches” – “in datagroup” <DATAGROUP> – at “request” time
(apply traffic on “remote” side of “external” interface)

Problem

This works correctly when the … Read more

F5 BIG-IP icon   F5 BIGIP – Modify URI path using local traffic policy



Im using my F5 BIGIP (v13) as reverse proxy to publish some websites by using local traffic policies. But i need to perform a URL rewriting. To be specific, i need to strip a string from the URI path.

It could be done using an IRule:

when HTTP_REQUEST{
if { [string tolower [HTTP::uri] ] starts_with "/path1" } {
  HTTP::uri [string 
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F5 BIG-IP icon   F5 BIG-IP – Rollback tmsh commands



Today a very short and simple post to learn how to rollback configurations performed via tmsh.
After executing some commands, if finally we need to undo those changes we can get it, at least, by the following ways:

    • In case of HA environment, the standby node configuration can be sync so that we set the active (changed) node to
Read more

F5 BIG-IP icon   F5 BIG-IP – Apply SNAT to client subnet or IP



In certain scenarios it can be interesting or necessary to apply SNAT only to certain client IPs when accesing a virtual server to  f.e. avoid assymetric routes, when the server gateway is not the F5… (take a look at this link for more examples).

These are the steps (im using BIG IP v13)…

Create a SNAT pool

I prefer the … Read more

F5 BIG-IP icon   F5 BIG-IP – Automate backup of configuration files



I have recently installed and configured my 2 node F5 BIG-IP cluster as load-balancer and SSL-VPN portal. I have been ocasionally performing configuration backups, but now i need to schedule them regularly and automatically.

This article covers the ways to perform the backup of a BIG-IP system and automate them.

Manual backup

Web GUI

In the menu options: System – Read more