Control: severity -1 important I discussed this at DebConf15 with Ritesh (and partially with Guido) and Ritesh and I came to the following conclusions:
- multipathd will synthesize events for all pre-existing devices on startup nowadays - so it will pick up all devices that are already there - no need for the udev rule anymore - but udev since a couple of versions (including that in Jessie) will lock the block devices it is currently processing with LOCK_SH, whereas multipath{,d} lock the block devices with LOCK_EX while they are trying to set up their mappings (to make sure that the same mapping isn't set up at the same time). But if one runs multipath as part of a udev rule, this will not work at all, because while any udev helper is run for a given block device, udev will have a LOCK_SH lock on it, and the multipath binary called from the helper will unsuccessfully try and try again to lock them with LOCK_EX, until udev runs into its timeout and kills multipath. Therefore, one should just get rid of the udev rule, because it doesn't work currently (due to udev locking), previously when it still worked was potentially slow if there were a lot of mappings, and is unnecessary with current multipathd, because mappings will just work with it. (Setting priority to important because it may cause boot to hang until the udev timeout is reached in certain circumstances.) Christian
signature.asc
Description: OpenPGP digital signature