Re: Strange behavior with carp and preemption
Hi Eli, > Eli K. Breen wrote: > Have you tried simply unplugging one's network cable? (to more closely > replicate what would happen during a hard lock or panic?) I should think > things won't be as smooth. Thats correct. When ifconfig down one IF, then it works and the backup becomes master on both interfaces. Not by unplugging the cable or power off the switch. That was what I wanted to test > Additionally, what happens if you shut the master down in to Single-User > mode? > I'm seeing a bug where if the MASTER is shutdown to single user mode it > stops the BACKUP from becoming MASTER. ...which is somewhat disturbing > as the original MASTER no longer actually performs any useful network > functions, but it does prevent takeover of the ARP address. > > Has anyone else tested/run in to this? This could be done in therory. Does the master send advertisements in single user mode? When no network is enabled I don't think, that it keeps being master. However, the problem reproduced by unplugging the cable, can be solved by workarounding using ifstated(8). :-( Best regards Ralf
Re: Strange behavior with carp and preemption
Hi list, I found out something new. > Ralf Hornik Mailings schrieb: > However, the advskew of carp1 on the master side keeps being zero, > allthough showing itself as BACKUP. Should ifconfig show advskew 240 then? tcpdump tells me although preemtion enabled an advskew of 0! After I look at ifconfig, the carp1 (which is the IF to preempt) tcpdump shows an advskew of 100 (which is the same value as the backup interface) but not 240! Could this be a bug in preemption? Has anyone else successfully set up carp with preemption? My OS is now OpenBSD 3.8 RELEASE. After going to stable, I'll be back! :-) Best regards Ralf
Re: Strange behavior with carp and preemption
Hi Nick, > Nick Holland wrote: > To the top of google we go! :) Great! :-) > are all the interfaces really in the carp group? Yes, I believe, because carp works if I shut down the Box, or something... > are the interfaces accurately and reliably detecting the cable-unplug? > Might some NICs (or their drivers) have trouble detecting that the cable > was suddenly unplugged, and thus, the change in advskew doesn't take When I unplug the cable or power off the switch, carp0 (what is the affected) goes into INIT and the carp1 goes into BACKUP. Then a can access the backup machine via carp0. So that works. However, the advskew of carp1 on the master side keeps being zero, allthough showing itself as BACKUP. Should ifconfig show advskew 240 then? That could be the problem... Thank you and Best regards! Ralf
Strange behavior with carp and preemption
Dear list, I set up two OpenBSD 3.7 -stable firewalls using carp. Everything works except preemption. When only one interface on the master side fails (pull the Cable) the regarding carp0 interface on the backup side becomes master. But not carp1. I waited some minutes, but carp1 keeps being backup until I do a simple ifconfig(8) on the master side. Then it changes immediately. I can reproduce it, waiting some minutes, or only a fiew seconds. Once I do an ifconfig on the master side, the backup side becomes master on all carp's. Strange...? My config: MASTER Side: # cat /etc/hostname.bge0 inet 10.25.0.2 255.255.255.240 # cat /etc/hostname.carp0 inet 10.25.0.1 255.255.255.240 10.25.0.15 vhid 1 pass foo carpdev bge0 # cat /etc/hostname.bge1 inet 10.25.0.18 255.255.255.240 # cat /etc/hostname.carp1 inet 10.25.0.17 255.255.255.240 10.25.0.31 vhid 2 pass foo carpdev bge1 # cat /etc/hostname.pfsync0 up syncif bge0 BACKUP Side: # cat /etc/hostname.bge0 inet 10.25.0.3 255.255.255.240 # cat /etc/hostname.carp0 inet 10.25.0.1 255.255.255.240 10.25.0.15 vhid 1 advskew 100 pass foo carpdev bge0 # cat /etc/hostname.bge1 inet 10.25.0.18 255.255.255.240 # cat /etc/hostname.carp1 inet 10.25.0.17 255.255.255.240 10.25.0.31 vhid 2 advskew 100 pass foo carpdev bge1 preemtion is enabled on both machines using sysctl -w net.inet.carp.preempt=1 and in /etc/sysctl.conf Can anybody reproduce it, and has a solution for this problem? Any help would be very nice! :-) Thanks Ralf
