Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
On Mon, Aug 13, 2007 at 03:36:11AM -0500, Abraham olivares Varela wrote: > Hi, > > Thanks for your answer , i only hava one last question. there is no such thing as a "last question" ;-) > I got two nodes one primary and one secondary like these: > > Node 1 connects to Node 2 by a switched network and Node 1 connects to Node 2 by a crossover cable. > Consider the following software configuration: > > DRBD communicates over the switched network and Heartbeat (HA) communicates over both networks. > Now, following these steps I can repeat the case when i have both nodes in a standalone state which > require user intervention to reconnect the current PRIMARY DRBD node. > > 1.) Node 1 is DRBD Primary and Node 2 is DRBD Secondary > 2.) I pull the switched network cable from node 1 > 3.) Node 1 detects the failure and HA moves the resources to > node 2 why? because of ping nodes? > 4.) Node 2 is now StandAlone->Primary/Unknown and node 1 is StandAlone->Secondary/Unknown > 5.) I reconnect the switched network cable from node 1 and it is at this moment when i got "split-brain". > > my question is, there is any posibility to avoid the "split brain" situation > when y reconnect the cable from node1? you can only "avoid" it in 3). you do so by configuring multiple heartbeat communication channels, and by using some outdate-peer handler. then node 2 would have known that it has outdated-data, and refused to become primary. in this scenario, once you actually do 3), you can no longer "avoid" "split brain situation". you can only "recover" from it later. -- : Lars Ellenberg Tel +43-1-8178292-0 : : LINBIT Information Technologies GmbH Fax +43-1-8178292-82 : : Vivenotgasse 48, A-1120 Vienna/Europe http://www.linbit.com : __ please use the "List-Reply" function of your email client.