This guide has been released to the DRBD community, and its authors The DRBD User’s Guide v. Pacemaker CRM configuration. This document will cover the basics of setting up a third node on a standard Debian Etch installation. At the end of this tutorial you will have a DRBD device that. There may be multiple resource sections in a single file. For more examples, please have a look at the DRBD User’s Guide.
|Published (Last):||12 October 2015|
|PDF File Size:||4.77 Mb|
|ePub File Size:||17.73 Mb|
|Price:||Free* [*Free Regsitration Required]|
Node identifiers can only be reasssigned in a cluster when the cluster is down. This means that applications e.
If a node becomes a disconnected primary, it tries to fence the peer’s disk. The default value isthe minimum Once more than max-buffers pages are in use, further allocation from this pool is throttled. You can find out which resync DRBD would perform by looking at the kernel’s log file.
As a consequence detaching from a frozen backing block device drdb terminates. Wait for connection timeout, if this node was a degraded cluster. If you use this option with any other file system, you are going to crash your nodes and to corrupt your data! Bring up the stacked resource, then make alpha the primary of data-upper:. But a large part of those will actually be still in sync, therefore using csums-alg will lower the required bandwidth in exchange for CPU cycles.
The available policies are io-error and suspend-io.
This section must contain a hosts parameter, which has the host names as arguments. These units are defined in the usual way e. With DRBD, we refer to the devices inside a resource as volumes.
Ubuntu Manpage: – DRBD Configuration Files
If the decision is to discard the data on the primary node, call the pri-lost-after-sb handler on the primary node. Larger values are appropriate for reasonable write throughput with protocol A over high latency networks. The size of the guise log is a major factor of how long a resync will take and how fast a replicated disk will become consistent after a crash.
Any blocks whose content differs from that of the corresponding block on the peer node will be marked out-of-sync in DRBD’s on-disk bitmap; they are not brought back in sync automatically.
Which machine runs crbd helper program is determined by the after-sb-0pri strategy. If later the local backing device “recovers”, and now DMAs some data from disk into the original request pages, in the best case it will just put random data into guie pages; but typically it will corrupt meanwhile completely unrelated data, causing all sorts of damage.
If the address parameter is not provided, no connections to peers will be created by default. Disables the use of disk flushes and barrier BIOs when accessing the meta data device. As as consequence, it should be abandoned.
The connection between the hosts uses protocol C. The handler is part of the fencing mechanism.
It can be set to any of the kernel’s data digest algorithms. Always honor the outcome of the after-sb-0pri algorithm. Note the resource is data-upper and the –stacked option is huide alpha only. During on-line verification, the contents of every block on the local node are compared to those on the peer node.
The start-sector will be rounded down to a multiple of 8 sectors 4kB.
With this option you request that the automatic after-split-brain policies are used as long as the data sets of the nodes are somehow related. If on-line verification is already in progress and this node is “VerifyS”this command silently “succeeds”.
As a consequence it should give up its primary role. Because the bitmap typically contains compact areas where all bits are unset clean or set dirtya simple run-length encoding scheme can considerably reduce the network traffic necessary for the bitmap exchange. Section path Parameters host name [ address [address-family] address ] [ port port-number ] Defines an endpoint for a connection. Sections common This section can contain each a diskhandlersnetoptionsand startup section.
For backward compatibilty reasons, and because on fast links this possibly does not improve transfer time but consumes cpu cycles, this defaults to off. The following sections are defined indentation indicates in which context: By defining a sync-after dependency, the resynchronization of this resource will start only if the resource res-name is already in connected state i.