Load Balancing Notes

Starting in, if I recall correctly, version 9.4.3 F5 introduced binary stores for configuration files. For those of us who enjoyed the access of files such as bigip.conf bigip_base.conf this made modifying these files impossible. Here is a technique that will allow you to modify and load both bigip.conf and bigip_base.conf.

If you were not aware /config/bigip.conf was the original configuration file that contains configuration elements that are shared between redundant devices (unit 1 and unit 2).

bigip_base.conf originally contained the configuration elements that are unique to a single device, such as VLANs, self IPs, default route for the management interface, etc…

Here are the commands for loading configuration from the command line:
This command dumps the configuration from memory:

b export filename.ext 

This command parses the target file to prove that it is compatible with the running configuration:

b verify load filename.ext

This command saves the newly loaded configuration into the memory resident database:

 b save all

This command loads the target file into the running configuration:

b import filename.ext 

This command merges the target file into a running configuration without altering existing configuration elements:

b merge filename.ext

I find it difficult to rename VLANs or to instruct customers how to rename VLANs for BIG-IP. So in an effort to make it easier I created this script. This intereactive script will replace the name of an existing VLAN with any valid name you choose.

#!/bin/bash

Pause()

{

        key=”"

        echo -n Hit any key to continue…

        stty -icanon

        key=`dd count=1 2>/dev/null`

        stty icanon

}

echo “Enter target VLAN name you wish to change”

read old_VLAN

echo “Enter new replacement VLAN name”

read new_VLAN

echo “Replacing VLAN “${old_VLAN?} “with VLAN “${new_VLAN?}

Pause

b export /var/tmp/bigipconfiguration

sed “s/^vlan $old_VLAN “‘{‘”$/vlan $new_VLAN “‘{‘”/” </var/tmp/bigipconfiguration.scf  >/var/tmp/newbigipconfiguration.scf

b import /var/tmp/newbigipconfiguration.scf