A question we see over and over again is
umountso slow? Why does it take so long?
DRBD 8.4.1 introduces a new feature:
read-balancing, which is configured in the
disk section of the configuration file(s). This feature enables DRBD to balance read requests between the Primary/Secondary nodes. Continue reading
Stumbling upon the Holy time-travellin’ DRBD, batman! blog post there’s only one thing to be said …
Be strict in what you emit, liberal in what you accept1
is simply not true when dealing with mission-critical systems.
It’s ok to be alerted on upgrading a machine because the “old, working” RegEx that did the parsing doesn’t match anymore2; it’s not a problem to get an email when someone adds the 100th DRBD resource and causes the grep to fail; and so on. Continue reading
The TL;DR version: don’t use
data-integrity-alg in a production setup. Continue reading
Depending on your setup and your workload (eg. within a virtual machine with little memory and much I/O) you could get into the situation that the kernel has little memory left, so wants to write some dirty pages to disk, but cannot, because for that it would need some memory free! Continue reading