Quick Setup for Gateway Failsafe

Posted by Nicholas Zurfluh on February 3, 2012
Posted in: F5 BIG-IP.

I found this in my notes…

The gateway fail-safe feature allows further redundancy between a failover pair of BIG-IP systems that point to different gateways. The gateway fail-safe feature allows each BIG-IP system to monitor the upstream gateway to which they are connected. If the gateway is marked down, the BIG-IP system can failover to its partner system to prevent further disruption to traffic.
Copy and paste the following commands:
b monitor ICMP_GWFailsafe ‘{
   defaults from gateway_icmp
   interval 2
   timeout 7
}’
b pool gateway_pool_unit1 ‘{
   min up members enable
   min up members 1
   min up members failover
   unit 1
   monitor all ICMP_GWFailsafe
   members x.x.x.x:any {}
}’
b pool gateway_pool_unit2 ‘{
   min up members enable
   min up members 1
   min up members failover
   unit 2
   monitor all ICMP_GWFailsafe
   members x.x.x.x:any {}
}’<CR>
Note: Replace x.x.x.x  with the IP address of your egress interface of your upstream router.
Save the gateway fail-safe pool configurations by typing the following command:
bigpipe save
Synchronize the configuration between the systems by typing the following command:
bigpipe config sync min
Reload the system configuration by typing the following command:
bigpipe load
To verify that the gateway fail-safe is now enabled, type the following command:
bigpipe ha table
You should see the pool min up member line, which indicates that the gateway fail-safe feature is enabled on the system.

Importing and Exporting Configurations

Posted by Nicholas Zurfluh on January 20, 2012
Posted in: F5 BIG-IP.

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

Renaming VLANs BIG-IP (LTM)

Posted by Nicholas Zurfluh on January 20, 2012
Posted in: F5 BIG-IP.

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