{"action":"created","issue":{"url":"https://api.github.com/repos/fdupoux/fsarchiver/issues/4","labels_url":"https://api.github.com/repos/fdupoux/fsarchiver/issues/4/labels{/name}","comments_url":"https://api.github.com/repos/fdupoux/fsarchiver/issues/4/comments","events_url":"https://api.github.com/repos/fdupoux/fsarchiver/issues/4/events","html_url":"https://github.com/fdupoux/fsarchiver/issues/4","id":124337879,"number":4,"title":"XFSv5 UUID change","user":{"login":"marcosfrm","id":12900645,"avatar_url":"https://avatars.githubusercontent.com/u/12900645?v=3","gravatar_id":"","url":"https://api.github.com/users/marcosfrm","html_url":"https://github.com/marcosfrm","followers_url":"https://api.github.com/users/marcosfrm/followers","following_url":"https://api.github.com/users/marcosfrm/following{/other_user}","gists_url":"https://api.github.com/users/marcosfrm/gists{/gist_id}","starred_url":"https://api.github.com/users/marcosfrm/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/marcosfrm/subscriptions","organizations_url":"https://api.github.com/users/marcosfrm/orgs","repos_url":"https://api.github.com/users/marcosfrm/repos","events_url":"https://api.github.com/users/marcosfrm/events{/privacy}","received_events_url":"https://api.github.com/users/marcosfrm/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":{"login":"fdupoux","id":11504382,"avatar_url":"https://avatars.githubusercontent.com/u/11504382?v=3","gravatar_id":"","url":"https://api.github.com/users/fdupoux","html_url":"https://github.com/fdupoux","followers_url":"https://api.github.com/users/fdupoux/followers","following_url":"https://api.github.com/users/fdupoux/following{/other_user}","gists_url":"https://api.github.com/users/fdupoux/gists{/gist_id}","starred_url":"https://api.github.com/users/fdupoux/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/fdupoux/subscriptions","organizations_url":"https://api.github.com/users/fdupoux/orgs","repos_url":"https://api.github.com/users/fdupoux/repos","events_url":"https://api.github.com/users/fdupoux/events{/privacy}","received_events_url":"https://api.github.com/users/fdupoux/received_events","type":"User","site_admin":false},"milestone":null,"comments":11,"created_at":"2015-12-30T11:44:44Z","updated_at":"2016-01-02T17:05:08Z","closed_at":null,"body":"XFSv5 filesystems have their UUID stamped on every metadata block and cannot have it changed by xfs_admin until xfsprogs 4.2.0 and kernel 4.3 (when sb_meta_uuid was added). Once configured, it will set an incompatible superblock flag to prevent older kernels from mounting the fs.\r\n\r\nhttp://oss.sgi.com/cgi-bin/gitweb.cgi?p=xfs/cmds/xfsprogs.git;a=commit;h=609f6bb20b7972c1a68370faea1dcbcf39912e07\r\n\r\nhttp://oss.sgi.com/cgi-bin/gitweb.cgi?p=xfs/cmds/xfsprogs.git;a=commit;h=9c4e12fb60c15dc9c5e54041c9679454b42cb23e\r\nhttp://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=ce748eaa65f2e9392ba82726503c8d994ffd6393\r\n\r\nIf mkfs.xfs had an option to define UUID at filesystem creation it would solve the problem. With the advantage of keeping both UUIDs, internal and \"visible\", in sync (no incompat flag) and, thus, preserving compatibility with older kernels, 3.15+ (`-m crc=1,finobt=0`) or 3.16+ (`-m crc=1,finobt=1`). Such an option does exist (`-m uuid=<UUID>`). Unfortunately it was only added in mkfs.xfs 4.3.0.\r\n\r\nhttp://oss.sgi.com/cgi-bin/gitweb.cgi?p=xfs/cmds/xfsprogs.git;a=commit;h=6af48b97f8ef7196e1303996995b3614dde24ec2\r\n\r\nIs an option for FSArchiver require mkfs.xfs >= 4.3.0 when restoring XFSv5 fs?"},"comment":{"url":"https://api.github.com/repos/fdupoux/fsarchiver/issues/comments/168407289","html_url":"https://github.com/fdupoux/fsarchiver/issues/4#issuecomment-168407289","issue_url":"https://api.github.com/repos/fdupoux/fsarchiver/issues/4","id":168407289,"user":{"login":"fdupoux","id":11504382,"avatar_url":"https://avatars.githubusercontent.com/u/11504382?v=3","gravatar_id":"","url":"https://api.github.com/users/fdupoux","html_url":"https://github.com/fdupoux","followers_url":"https://api.github.com/users/fdupoux/followers","following_url":"https://api.github.com/users/fdupoux/following{/other_user}","gists_url":"https://api.github.com/users/fdupoux/gists{/gist_id}","starred_url":"https://api.github.com/users/fdupoux/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/fdupoux/subscriptions","organizations_url":"https://api.github.com/users/fdupoux/orgs","repos_url":"https://api.github.com/users/fdupoux/repos","events_url":"https://api.github.com/users/fdupoux/events{/privacy}","received_events_url":"https://api.github.com/users/fdupoux/received_events","type":"User","site_admin":false},"created_at":"2016-01-02T17:05:08Z","updated_at":"2016-01-02T17:05:08Z","body":"Ok I have implemented this change in the new branch."}}