On Tue, Oct 7, 2014 at 6:21 PM, Lee Duncan <ldun...@suse.com> wrote: > I am debugging a problem where the symlinks in /dev/disk/by-path > disappeared for iSCSI target devices. > > It looks like it's from systemd/udev commit > e98bbfd2074e2b1079b7059341eac25741baf319 > > udev: path_id - suppress ID_PATH for devices with an unknown parent device > type > > I believe the worry was that if you allowed pathnames based on a > parent bus that did not supply unique IDs, then you could end up with > duplicate paths, since this references a bug: > > https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1321816 > > But, looking at the code, this change seems to have assumed SCSI was > not a "supported parent". I am not aware of any cases where SCSI has > given duplicate names to devices
It is not about non-conflicting numbers, it is about predictability of the numbers. The SCSI enumeration numbers are not predictable and depend on enumeration or discovery order. The numbers used in by-path links would need to be able to be calculated before the device is connected. The by-path links with non-predictable numbers are pointless and wrong to create. It is expected that only a very limited subset of devices support by-path, there is nothing wrong if iSCSI does not have them. While we are at it: all specialized SCSI code should move to its own package and out of the systemd/udev source tree. We will not extend any SCSI handling in udev, we just cannot support it. Hannes already started to work on moving things to sg3_utils. Hannes, any update on this? Thanks, Kay _______________________________________________ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
