When teaching the F5 admin class last week, there is a lab to use cookie persistence. In order to configure this feature, you need to apply a cookie persistence profile. Yet, most students didn’t realize that there is profile dependence in the F5 configuration.

As this feature is obviously on top of the HTTP protocol which is using the TCP protocol. Under the virtual server configuration, when you select the destination port as port 80, it automatically applies the TCP profile. However, the HTTP profile is not by default selected. So if you directly apply the cookie persistence profile (Local traffic > Virtual Server > Resources) without the HTTP profile, it will produce an error.

But sometimes the error message has been overlooked!

So in order to fix this, you need to go back to the Local traffic > Virtual Server > Properties screen.

Under the HTTP profile, need to select one of the HTTP profile, then update.

Then go back to the resources screen, apply the cookie persistence profile.

Recently, I have tested the F5 (Big IP) LTM v11.4 SNMP configuration and my snmpscan tools. Here is the steps. 

1. In the F5 LTM admin webpage, select the SNMP->Agent->Configuration

2. In the configuration page, need to add your SNMP management software subnet (or starting octets).

3. Then go to the "access (v1,v2c)" screen (of course can use v3). Create a new access.

4. In the access creation screen, you define the community string. Yet, what I want to point out is that if you want to restrict the OID branch that this community allows, first the OID syntax begins with a dot. E.g. for MIB-2, enter ".1.3.6.1.2.1". Secondly, need to select the source IP  that allow access.

5. Now, you can download my free snmpscan tools under IPtools. Enter the IP of your F5, comunity and OID. Click the start scan, now you get the values of the MIB tree branch as below: