Re: CARP issue with 2 Masters
Hi Matthew That did the trick, have accidentally been using an old pre-carp set of firewall rules for the last few days. After your response, I went back and updated to the new rule-set. It's always the simple things. Thank you, your response was greatly appreciated. Frank > > I have CARP running on a master and a slave server and for some unknown > reason > > the slave continues to classify itself as a master, even though the > advskew is > > higher than on the master. > > It appears that queries sent to the CARP ip address go to the master 50% > of the > > time and the slave 50% of the time when both servers are up. This plays > havoc > > with my databases as I synchronise them asynchronously. > > > > When I take the carp interface down on the slave using 'ifconfig carp0 > down && > > ifconfig carp0 up' it lists it's status as 'backup' for about 10 seconds > and > > then goes back to 'master'. > > Have you by any chance firewalled out the multicast packets that CARP uses > 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 > master. > > 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 > > -- > Dr Matthew J Seaman MA, D.Phil. 7 Priory Courtyard > Flat 3 > PGP: http://www.infracaninophile.co.uk/pgpkey Ramsgate > Kent, CT11 9PW > > Come and visit Web Prophets Website at http://www.webprophets.net.au ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
CARP issue with 2 Masters
Hi I have CARP running on a master and a slave server and for some unknown reason the slave continues to classify itself as a master, even though the advskew is higher than on the master. It appears that queries sent to the CARP ip address go to the master 50% of the time and the slave 50% of the time when both servers are up. This plays havoc with my databases as I synchronise them asynchronously. When I take the carp interface down on the slave using 'ifconfig carp0 down && ifconfig carp0 up' it lists it's status as 'backup' for about 10 seconds and then goes back to 'master'. Both servers run identical versions of FreeBSD 7.0 with all the same installed ports on identical hardware. The kernel has the following differences from the standard amd64 kernel: ident DBKERNEL options SCHED_ULE device carp The standard kernel includes "options PREEMPTION" which is mentioned as a possible problem in the handbook with the slave not relinquishing the ip address when the master comes back, but that's not exactly what I'm getting here. Here are the relevant setup details for the boxes. MASTER uname -a FreeBSD dbmaster.xxx.net 7.0-RELEASE-p5 FreeBSD 7.0-RELEASE-p5 #1: Fri Oct 3 13:54:35 EST 2008 [EMAIL PROTECTED]:/usr/obj/usr/src/sys/DBKERNEL amd64 /etc/rc.conf ifconfig_em2="inet 192.168.2.11 netmask 255.255.255.248" cloned_interfaces="carp0" ifconfig_carp0="vhid 1 pass mypassword 192.168.2.10/29" ifconfig em2: flags=8943 metric 0 mtu 1500 options=9b ether 00:14:22:20:b0:dc inet 192.168.2.11 netmask 0xfff8 broadcast 192.168.2.15 media: Ethernet autoselect (100baseTX ) status: active carp0: flags=49 metric 0 mtu 1500 inet 192.168.2.10 netmask 0xfff8 carp: MASTER vhid 1 advbase 1 advskew 0 SLAVE uname -a FreeBSD dbslave.xxx.net 7.0-RELEASE-p5 FreeBSD 7.0-RELEASE-p5 #1: Fri Oct 3 13:54:42 EST 2008 [EMAIL PROTECTED]:/usr/obj/usr/src/sys/DBKERNEL amd64 /etc/rc.conf ifconfig_em2="inet 192.168.2.12 netmask 255.255.255.248" cloned_interfaces="carp0" ifconfig_carp0="vhid 1 advskew 200 pass mypassword 192.168.2.10/29" ifconfig em2: flags=8843 metric 0 mtu 1500 options=9b ether 00:14:22:1d:15:d0 inet 192.168.2.12 netmask 0xfff8 broadcast 192.168.2.15 media: Ethernet autoselect (100baseTX ) status: active carp0: flags=49 metric 0 mtu 1500 inet 192.168.2.10 netmask 0xfff8 carp: MASTER vhid 1 advbase 1 advskew 200 With the advskew on the 'slave', I've tried values of 100, 200, 230, 240 and 250 with no difference in performance. I've also tried ifconfig_carp0="vhid 1 advskew 200 pass mypassword backup 192.168.2.10/29" on the slave but this simply locks it into INIT. I can't figure out if I missed a step in the documentation, made a silly mistake in my setup, or found a bug. Any help would be greatly appreciated. Thank you Come and visit Web Prophets Website at http://www.webprophets.net.au ___ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"
