How does the mcp daemon work together with bigip.conf, mcpdb.bin and the running configuration?

Hey guys!

 

The background to this question is the scenario for when the binary configuration (mcpdb.bin) and the text configuration (bigip.conf) gets out of sync. The scenario and soloution is presented in the following SOL13030: Forcing the mcpd process to reload the BIG-IP configuration

 

According to the SOL article, from BIG-IP version 9.4.0 and onwards, mcpd process loads the text configuration files (bigip.conf and bigip_base.conf) into the running configuration during the first boot up and builds a binary configuration image. These are created into the two files:

 

• /var/db/mcpdb.bin
• /var/db/mcpdb.info

It does this in order to faster load the configuration without needing to parse and validate the configuration.

 

As the above statement says, the mcpd process builds the binary configuration image during first boot but how does it work after the first bootup?

 

When you make a configuration change using the WebGUI, does the BIG-IP system save configuration to the running configuration, text configuration AND the binary configuration?

 

How can a mismatch between the binary and the text configuration occur in the first place?

 

In our case there are configuration from over a month ago that is mismatching. The binary configuration complains that objects are missing that was removed over a month ago that is not present in the bigip.conf file.

 

What causes such a long delay of the configuration mismatch?

 

Thanks!