On Tue, Nov 14, 2023 at 10:44:02AM +0000, Martin Wilck wrote: > I haven't looked into "system.devices" so far. Is there a high-level > description of this feature available somewhere? A link would be > appreciated. On (open)SUSE, afaik, system.device is not used (Heming, > correct me if I am wrong). https://man7.org/linux/man-pages/man8/lvmdevices.8.html If that's too low-level let me know and I'll look at writing something more conceptual and introductory. > > - To make filter-mpath use udev info, and prevent lvm from using > > wwids, you can set external_device_info_source=udev and > > multipath_wwids_file="". > > Good to know, but that's kind of counter-intuitive. I'd prefer > if external_device_info_source=udev did what the name says, and a new > mode ("external_device_info_source=hybrid", say) was introduced for the > current behavior. I'd also thought about adding a new option for external_device_info_source that would mean "udev info only", rather than "both native and udev info." The complication is that external_device_info_source applies to a few different kinds of device info, not just multipath, and I doubt we can apply only udev info to all those cases. This means adding another config option... not much different from just using multipath_wwids_file="". > Can a distribution set multipath_wwids_file="" by default without > undesired side effects? Yes, it just causes lvm to skip the use of /etc/multipath/wwids for checking if a device is a multipath component. Dave
