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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p><span style='color:#1F497D'>Good afternoon,<o:p></o:p></span></p><p><span style='color:#1F497D'>I recently asked a question regarding resource stickiness. In particular, I set up two nodes with DRBD. San1 was initially set primary while san2 was secondary. When I brought san1 down, san2 was promoted to primary. However, when I brought san1 back online, it was promoted back to primary. Ideally, I wanted to keep san2 as primary to avoid the unnecessary work of moving the resources back. Well, I found the source of my problem and it was definitely not pacemaker. I wanted to document this in hopes that it might save other people considering pacemaker some trouble during testing (and it might help others on this list diagnose strange problems).<o:p></o:p></span></p><p><span style='color:#1F497D'>My test nodes were actually virtual machines. In itself this would not normally be a problem. But, I was simulating a node failure by pausing the virtual machine. When I paused san1, it would be taken off-line and san2 would be promoted. When I resumed san1, it would come back online as if nothing happened. All its resources were configured identically (DRBD master, mounted filesystem). This is the part that I was missing.<o:p></o:p></span></p><p><span style='color:#1F497D'>When pacemaker noticed this new node coming back online preconfigured, it simply gave back control to san1. Actually, pacemaker made the most effective choice here. Unfortunately, if you are not paying attention to what you are doing, the choice looks like it is violating resource stickiness.<o:p></o:p></span></p><p><span style='color:#1F497D'>I guess if it were not for the fact that san1 was paused, this would have actually created a split brain.<o:p></o:p></span></p><p><span style='color:#1F497D'>So, this is obviously not one of my brightest moments. Many of you may be thinking "duh". I just wanted to bring this to light in case anyone else runs into it.<o:p></o:p></span></p><p><span style='color:#1F497D'>For what it is worth, one can test the setup properly by actually shutting the virtual machine down (rather than pausing it). When the node is brought back online, it will have all the resources disabled. This gives pacemaker a chance to bring up DRBD in secondary mode.<o:p></o:p></span></p><p><span style='color:#1F497D'>Thank you everyone for your help,<o:p></o:p></span></p><p><span style='color:#1F497D'> Ted<o:p></o:p></span></p><p><span style='color:#1F497D'><o:p> </o:p></span></p><p><span style='color:#1F497D'><o:p> </o:p></span></p><p><span style='color:#1F497D'><o:p> </o:p></span></p></div></body></html>