A question we see over and over again is
Why is
umountso slow? Why does it take so long?
Part of the answer was already given in an earlier blog post; here’s some more explanation. Continue reading
“umount is too slow”
Reply
Tag Archives: drbd
DRBD 8.4.3: faster than ever
For the people who don’t already have DRBD 8.4.3 deployed: here’s another good reason — Performance. Continue reading
Change the cluster distribution without downtime
Recently we’ve upgraded one of our virtualization clusters (more RAM), and in the course of this did an upgrade of the virtualization hosts from Ubuntu Lucid to RHEL 6.3 — without any service interruption. Continue reading
Raspberry Tau: a Pi cluster
The Raspberry PI is a small ARM computer (hardware specifications in wiki, outline and FAQs). Of course, you can build a cluster with it! Continue reading
Mirrored SAN vs. DRBD
Every now and then we get asked “why not simply use a mirrored SAN instead of DRBD”? This post shows some important differences. Continue reading
Best Practice: Use Backup with your DRBD cluster!
We want to take an opportunity to explain LINBIT’s best practices in regards to DRBD and backup procedures.
“read-balancing” with 8.4.1+
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
LINBIT participates in the German Cloud (“Deutsche Wolke”)
Deutsche Wolke (“German Cloud”) was founded to establish Federal Cloud Infrastructure in Germany.
This infrastructure will provide additional legal and security protections for hosted data. No longer will small businesses be exposed to the legal risk of losing their website presence without a trial (an unfortunate reality when doing business on transatlantic clouds).
The natural partner for backend storage infrastructure is LINBIT; as authors and maintainers of DRBD, we are best suited to provide the technical expertise to achieve High Availability. Also, DRBD Proxy is the obvious choice for off-site or disaster recovery replication (from the office into the cloud).
We at LINBIT look forward to seeing this project grow and prosper!
Monitoring: better safe than sorry…
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
Maximum volume size on DRBD
From time to time we get asked things like this:
I want to use a 10TiB volume with DRBD, is that supported”?
The easiest way to answer things like that is to say look for yourself on the public DRBD usage page – the biggest public device size is ~220TiB, so go figure 
Continue reading