1. In RHEL4 U2, when a device alias is created by modifying /etc/multipath.conf file, the new DM device is created along with the existing DM device for which the alias is created. Both devices exist in /dev/mapper/ directory. When “multipath –ll” is executed, both original device and the device with alias name are displayed. We can have different device policies like path grouping etc for both of these devices. User need to either reboot or run “multipath –f <wwid> to remove the existing device for which alias was created. I think we should have only one device when alias is created. Any suggestions? This is not a problem as user can go and delete/flush the original device.
2. Blacklisting of the device is possible using “wwid <wwn>” in blacklist block in /etc/multipath.conf. Is there any way to blacklist the device created with alias? Giving an alias name in devnode or wwid doesn’t seem to work.
3. As it is not encouraged dmsetup utility to be used for multipathing devices, features like suspend and resume will be useful in bringing down the device for maintenance purposes. Any thoughts?