<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=us-ascii"> <meta name="Generator" content="Microsoft Exchange Server">  <style></style> </head> <body> <font face="Arial, sans-serif" size="2"> <div>Hi all,</div> <div> </div> <div>In our testing with DM RDAC stack with RHEL 5 (including 5.5 and 5.4), we found that manual failback doesn't work as expected.</div> <div> </div> <div>What we did is to connect the host to Dell PowerVault 3200/i array. After everything is configured, we changed "failback" value for our device from "immediate" to "manual". Then the host is rebooted for the new value to take effect. However, automatic failback still happens once failed path is restored. It seems failback "manual" doesn't work.</div> <div> </div> <div>We've also verified deferred failback works as expected. So "manual" failback seems to be the only issue. </div> <div> </div> <div>Our device section in multipath.conf is as follows:</div> <div> </div> <div>...</div> <div><font face="Courier New">device {</font></div> <div><font face="Courier New"> vendor "DELL"</font></div> <div><font face="Courier New"> product "MD32xxi"</font></div> <div><font face="Courier New"> path_grouping_policy group_by_prio</font></div> <div><font face="Courier New"> prio rdac</font></div> <div><font face="Courier New"> polling_interval 5</font></div> <div><font face="Courier New"> path_checker rdac</font></div> <div><font face="Courier New"> path-selector "round-robin 0"</font></div> <div><font face="Courier New"> hardware_handler "1 rdac"</font></div> <div><font face="Courier New"> failback manual</font></div> <div><font face="Courier New"> features "2 pg_init_retries 50"</font></div> <div><font face="Courier New"> no_path_retry 30</font></div> <div><font face="Courier New"> rr_min_io 100</font></div> <div><font face="Courier New"> prio_callout "/sbin/mpath_prio_rdac /dev/%n"</font></div> <div><font face="Courier New"> }</font></div> <div>…<br> </div> <div>Any sugegstion or insight on this issue?</div> <div> </div> <div>Thanks,</div> <div>Yanqing</div> <div> </div> </font> </body> </html>