Oracle Linux: Insufficient memory to auto-enable kdump

Remember how I said “you should be all set”, last week? Turns out, I was only partially right. After creating a local user account, Linux also configures kdump, the kernel crash dumping mechanism. When attempting to do so, it returned this error message:

As problems go, this one is fairly minor. Kdump does not need to be enabled or configured for everything else to work. I made a note of the issue, and clicked right through the error, and logged in. That said, I really don’t like leaving stuff like that without looking into resolving it. I immediately grokked that system-config-kdump refers to a shell command, opened terminal, and entered the command. It opened this window:

I proceeded to click “Enable”, and then “Apply”. The system asked for a reboot, and then prompted for the root password, three times. After that, it returned the following error:

At a hunch, I increased the kdump memory to 160 MB, then tried to apply once more. After being prompted for root password thrice, the settings were saved. Peculiarly, kdump memory was set to its original 128 MB. Following a reboot, I checked, and kdump was up and running, kdump memory still set to 128 MB.