Housekeeping and kernel upgrades do not always make for happy bedfellows

Who, Me? You can't hurry Linux kernel upgrades, as The Supremes never sang and a Register reader discovers in today's episode of Who, Me?

Our story, from a reader Regomised as "Aapt", takes us back to the days when the DEC Alpha reigned, er, supreme over computer labs and anyone with even a passing knowledge of Linux could fall all too easily into the "expert" bucket.

Aapt was not short on confidence, be it tinkering with the xconfig file to persuade a monitor to work with Linux or, as we shall see, casually attempting a kernel upgrade. "I was convinced I was the best sysadmin for my lab computers," he told us.

Since finding a decent sysadmin for Linux was problematic back in the last century, and the institute where he worked had yet to do so, Aapt fell into the role. "For 'best sysadmin' read 'only sysadmin', for whatever I was worth," he said, with the wisdom of decades now under his belt. "Thank goodness they didn't ask me to administer any other institute machines..."

Thank goodness indeed.

Aapt's little world consisted of a lab containing a mighty DEC Alpha workstation, which performed compute and fileserver tasks, and a bunch of x86 machines that he considered poor performers in comparison. The Alpha had, after all, run without a reboot for over year. The same could not be said for the other hardware.

Eventually, however, the time came to upgrade the Linux kernel.

"I didn't back up the OS because, after all, I was going to upgrade it, wasn't I?"

The new kernel was compiled and made ready to be placed on the required partition.

A tidy fellow, Aapt decided that the upgrade would also be a good time to clear out all the system files.

"In a fit of enthusiasm, I set off the dreaded rm -rf on the /usr partition."

For those unaware, the rm command deletes files. Adding the -r option removes directories and their contents recursively. The -f option stops prompts before removal.

"I sat back meditatively," he said, "listening to the crunching sound of the disk head skittering around killing all those bits.

"Fortunately, this took long enough for my meditations to come to the point of thinking about the relative merits of pointing the bootloader to the new kernel vs a complete reinstall from scratch."

Aapt had been through the delight of an Alpha install over a year previously and the experience had "Not Been Fun."

Gut-swooping moment of fear upon him, he frantically jabbed Ctrl-C until the destruction abated. How much of the system had survived?

"The great Penguin in the Sky smiled upon me," he said, after gingerly trying a few commands (presumably not rm -rf this time) to see what remained. Enough, just, to complete the upgrade and update the system files.

"I never told anyone about my nearly successful attempt to delete my OS while it was running," he said.

"I'll just say that this experience substantially reduced any reluctance I may have had to hand things over to the institute sysadmin, when we finally hired one."

We have fond memories from the last century of an overpromoted DBA insisting that using DEL *.* on a running SQL Server would be fine since SQL locked .MDF files and .LDF files. Oh how we laughed when we discovered that backups hadn't been taken first.

How about you?

Share your tale of the moment you realised you didn't really know what you were doing after all with an email to Who, Me? ®