Skip site navigation (1)Skip section navigation (2)
Date:      Sun, 05 Oct 2008 11:11:30 +0100
From:      Matthew Seaman <m.seaman@infracaninophile.co.uk>
To:        frank.cam@webprophets.net.au
Cc:        questions@freebsd.org
Subject:   Re: CARP issue with 2 Masters
Message-ID:  <48E892D2.6050409@infracaninophile.co.uk>
In-Reply-To: <1223198445.48e886ede1ea7@webmail.webprophets.net.au>
References:  <1223198445.48e886ede1ea7@webmail.webprophets.net.au>

next in thread | previous in thread | raw e-mail | index | archive | help
This is an OpenPGP/MIME signed message (RFC 2440 and 3156)
--------------enigA04EDA0AFBBC8B5BAEDA4C58
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: quoted-printable

frank.cam@webprophets.net.au wrote:

> I have CARP running on a master and a slave server and for some unknown=
 reason=20
> the slave continues to classify itself as a master, even though the adv=
skew is=20
> higher than on the master.=20
> It appears that queries sent to the CARP ip address go to the master 50=
% of the=20
> time and the slave 50% of the time when both servers are up. This plays=
 havoc=20
> with my databases as I synchronise them asynchronously.
>=20
> When I take the carp interface down on the slave using 'ifconfig carp0 =
down &&=20
> ifconfig carp0 up' it lists it's status as 'backup' for about 10 second=
s and=20
> then goes back to 'master'.

Have you by any chance firewalled out the multicast packets that CARP use=
s
to test for interface death?  If either one of a CARP pair can't see CARP=
 packets
frequently enough it will think the other is down and promote itself to m=
aster.

If your firewall is blocking, then add a rule like this on both machines:=


pass quick on $ext_if proto carp \
    from $ext_if:network to $carp_mcast keep state

$carp_mcast is defined as "224.0.0.18"

	Cheers,

	Matthew

--=20
Dr Matthew J Seaman MA, D.Phil.                   7 Priory Courtyard
                                                  Flat 3
PGP: http://www.infracaninophile.co.uk/pgpkey     Ramsgate
                                                  Kent, CT11 9PW


--------------enigA04EDA0AFBBC8B5BAEDA4C58
Content-Type: application/pgp-signature; name="signature.asc"
Content-Description: OpenPGP digital signature
Content-Disposition: attachment; filename="signature.asc"

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.9 (FreeBSD)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org

iEYEAREIAAYFAkjoktgACgkQ8Mjk52CukIwz6gCggMWJ3yZmwbodC8uJcRTyrASr
obUAn2e/vci+mclsGHFDBDnjH5n8FHtQ
=u8UF
-----END PGP SIGNATURE-----

--------------enigA04EDA0AFBBC8B5BAEDA4C58--



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?48E892D2.6050409>