Remus Toolkit Differences

From Xen

Remus in XL

Xen 4.5 and newer

In 4.5 the XM toolstack is not supported any more. Remus is invoked via the "xl remus ..." syntax. This syntax can be found in recent xl man pages for Xen 4.5 (search for the "remus" option). Also see Xen Man Pages, which lists manuals for all Xen releases.

If you work with Xen unstable (development branch), check out xl man pages for unstable

For your convenience, we copied a section of the Xen 4.5 xl man pages for Remus into this page

Usage: xl remus [OPTIONS] domain-id host

OPTIONS
-i MS            Checkpoint domain memory every MS milliseconds (default 200ms).
-u               Disable memory checkpoint compression.
-s sshcommand    Use <sshcommand> instead of ssh. String will be passed to sh. If empty, run <host> instead  
                 of ssh <host> xl migrate-receive -r [-e].
-e               On the new host, do not wait in the background (on <host>) for the death of the domain. 
                 See the corresponding option of the create subcommand.
-N netbufscript  Use <netbufscript> to setup network buffering instead of the default script 
                 (/etc/xen/scripts/remus-netbuf-setup).
-F               Run Remus in unsafe mode. Use this option with caution as failover may not work as intended.
-b               Replicate memory checkpoints to /dev/null (blackhole). Generally useful for debugging. 
                 Requires enabling unsafe mode.
-n               Disable network output buffering. Requires enabling unsafe mode.
-d               Disable disk replication. Requires enabling unsafe mode.

Xen 4.4.

Xenlight is the current toolkit for Xen Project. In xenlight, Remus is invoked via the "xl remus ..." syntax. This syntax can be found in recent xl man pages (search for the "remus" option).

As of 4.4, Remus support in xl is still in experimental (proof-of-concept) phase. Per the man page, there is no support for network or disk buffering in the current release.

Remus in XM (Xen 4.4 or older)

Remus was originally implemented when Xen Project was using the xm toolkit. If you are still using xm, you will need to use the "remus" command to control the software.

The "remus" command uses the following syntax:

Usage: remus [options] domain [destination]
Options:
 -h, --help            show this help message and exit
 -i MS, --interval=MS  checkpoint every MS milliseconds
 -p PORT, --port=PORT  send stream to port PORT
 --blackhole           replicate to /dev/null (no disk checkpoints, only
                       memory & net buffering)
 --no-net              run without net buffering (benchmark option)
 --no-compression      run without checkpoint compression
 --timer               force pause at checkpoint interval (experimental)