How reliable is DRDB?

What are the restrictions on its use? What is the speed of its work compared to a local disk? Is this an acceptable replacement for expensive SAN-based solutions for an average project size (data less than a terabyte)? Read more

DRBD dual primary + iscsi multipath?

Question: if a resource is synchronous (protocol Z) is replicated between two servers, each of which has an independent iscsi target for this resource, can these two targets be exported as a single resource using mutipath? Reading Lkml has so far suggested that the synchronization mode is important. What other moments might be? Read more

DRBD - poor write performance?

Hello. I have the following config: 2 x IBM x3630, 14 2Tb SATA-disks in each, on each raid10 of 12 disks is assembled, 2 in hot-spare. Gigabit link between servers. DRBD over raid10 devices (md-raid). Productivity / dev / md127: throughput ~ 900 MB / s fio with the following config: config fio [readtest] blocksize=4k filename=/dev/md/raid10 rw=randread direct=1 buffered=0 ioengine=libaio iodepth=16 gives the following numbers: fio readtest: (groupid=0, jobs=1): err= 0: pi... Read more

Is it possible to make DRBD analogue from iSCSI?

Good day! In the distributive that you plan to use, there is no support for DRBD, there is only iSCSI. I want to organize block redundancy over the network from one server to another, so that if the main one fails, they have an exact copy of the first server data. Is it possible to? Read more

Dual-primary DRBD: why exactly ocfs2 / gfs / another cluster FS?

Why is it necessary to use cluster fs, for example ocfs2, when deploying DRBD, both nodes of which are operating in Primary mode, for normal operation? When using ext3, synchronization occurs, but only after remounting the partition, as if the file table is not transferred from the first node to the second. For example, at 1 node we delete the file 1.txt, at 2 node in the output of ls it is present, but an attempt to open it fails. Remount the partition on 2 node and the file disappears. Why... Read more

Why is PostgreSQL not running on the master node of Pacemaker?

There is a Pacemaker cluster with some resources. The configuration is as follows: node sky01 \ attributes standby="off" node sky02 primitive drbd_fs ocf:heartbeat:Filesystem \ params device="/dev/vg1/cluster" directory="/cluster" options="noatime,nodiratime" fstype="xfs" \ op start interval="0" timeout="60" \ op stop interval="0" timeout="120" primitive drbd_sky ocf:linbit:drbd \ params drbd_resource="sky" \ op monitor interval="15" \ op ... Read more

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