2011-06-07 00:01:00
If your BoKS master server ever inexplicably grinds to a halt, blocking all suexec and remote logins, just do a ps -ef to check if there's anybody running a dumpbase. Then pray that you can contact this person, or that there's still someone with a root shell on the server...
A running dumpbase process keeps a read/write lock on the BoKS database until it has dumped all the requested content. If you have a sizeable database a full dump can take half a minute or more. That's not awful and it won't affect your daily operations too much, but it should still be kept to a minimum.
But what if? What if someone decides to run dumpbase and then pipe it through something like more?
The standard buffer size for a pipe is roughly 64kB (some Unices might differ). This means that dumpbase will not finish running until you've either ^C-ed the command, or until you've more-ed through all of the pages. Thus the easiest way to completely lock your master server, is to more a dumpbase and then go get yourself a cup of coffee. Because not even root will be able to login on the console while the dumpbase is active.
kilala.nl tags: boks, sysadmin,
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