I have been using the CyanogenMod Recovery partition to install custom ROMs, but with my stock Android 2.3.6 ROM, I was having an issue where the Recovery partition is getting restored with stock one with very next boot. This issue is also mentioned in notes for CM Recovery installation (http://wiki.cyanogenmod.org/w/Install_CM_for_passion):
Note: Some ROMs overwrite recovery at boot time so if you do not plan to immediately boot into recovery to install CyanogenMod, please be aware that this may overwrite your custom recovery with the stock one.
Though it was not a show-stopper as it gets fixed once I install the custom ROM, but what if you plan to use this recovery, but keep using the stock ROM. Fortunately, the solution for this is simple too. As mentioned above in the warning note, the Stock 2.3.6 ROM tries to restore the Recovery during the boot. The recovery backup is stored at the following path in System:
So, all you have to do to get rid of this automatic recovery overwrite is to delete this recovery backup file, and Android system will no longer overwrite. your custom recovery image. You can delete this file easily using ES File Explorer. If you have never used ES File Explorer, here is quick tutorial to do this:
1. Open ES File Explorer File Manager.
2. Select the menu button on your device and click on Settings.
3. Check the Up to Root option, then also check the Root Explorer option. When the prompt appears for root privileges, press the 4. Allow/Grant button.
5. Check the Mount File System option as well.
6. Go to the Root folder of your Android file-system i.e. “/” path.
7. Go to the “system” folder and long-tap on the recovery-from-boot.p file, and then delete it.
I hope you find this of help.