[Pacemaker] Quick question regarding wiki vs 'Clusters from Scratch v2'

[Andrew Beekhof]

On Thu, Aug 2, 2012 at 9:20 AM, mark - pacemaker list
<m+pacemaker at nerdish.us> wrote:
> Good afternoon,
>
> Looking at the corosync configuration examples on the wiki (
> http://www.clusterlabs.org/wiki/Initial_Configuration ) and in the Clusters
> from Scratch document (
> http://www.clusterlabs.org/doc/en-US/Pacemaker/1.1/html/Clusters_from_Scratch/_sample_corosync_configuration.html
> ), there are a number of changes or omissions of settings.
>
> The wiki example includes:
>
>        token: 5000
>         token_retransmits_before_loss_const: 20
>         join: 1000
>         consensus: 7500
>         vsftype: none
>         max_messages: 20
>         clear_nod_high_bit: yes
>
> ... and a few other settings that are no longer in the CfSv2 document.  The
> corosync.conf example there is very close to the default configuration when
> building from source.  It no longer covers creating a service definition in
> /etc/corosync/services.d/, because that's no longer needed and instead
> corosync and pacemaker are started individually.  What about the other
> settings, though?  I noticed with the CfSv2 sample config only (altered for
> my network), I get negative node ids since it doesn't include the
> 'clear_node_high_bit' setting.  Does that have no negative repercussions
> with pacemaker?

Pacemaker uses uint32_t for storing the nodeid, so no it doesn't care.
It does make the logs annoying though since not everyone uses %u
everywhere (which correctly interprets the first bit to NOT indicate a
negative number).
And if you're using OCFS2 and possibly GFS2, its still a good idea.

> Are any of those other more conservative timing settings
> still relevant, or is it pretty safe to just tweak the example configuration
> and let corosync and pacemaker do their thing with largely default values?

Pretty much.
The conservative timings came from a time when I was running clusters
with 8+ nodes.
Most people aren't doing that and its a few less things for admins to
think about :)