I've restored my system to a working state by building lvm2 from upstream source that includes the referenced patch and using the compiled lvm to do a config backup which added the missing metadata attributes then using native lvm (lvm2 2.02.133-1ubuntu7) to restore the config backup.
All is working now using lvm2 2.02.133-1ubuntu7 package. guy@mediaserver:~/tools$ sudo lvs LV lv_cache has invalid cache's feature flag. LV lv_cache is missing cache policy name. Internal error: LV segments corrupted in lv_cache. guy@mediaserver:~/tools$ sudo ./lvm vgcfgbackup -v Using volume group(s) on command line. Cache is missing cache policy, using mq. Cache is missing cache mode, using writethrough. Creating volume group backup "/etc/lvm/backup/vg1" (seqno 13). Volume group "vg1" successfully backed up. guy@mediaserver:~/tools$ sudo vgcfgrestore vg1 Restored volume group vg1 guy@mediaserver:~/tools$ sudo lvs LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert media vg1 Cwi---C--- 500.00g [lv_cache] [media_corig] -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1556602 Title: LVM in 16.04 cannot mount LVM Cached Volumes created in 15.10 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lvm2/+bug/1556602/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs