diff options
author | Kotresh HR <khiremat@redhat.com> | 2017-11-13 05:27:50 -0500 |
---|---|---|
committer | Aravinda VK <avishwan@redhat.com> | 2017-11-14 11:13:57 +0000 |
commit | 6e2ce37341e5d600d8fd5648b39eec0dbdbe45ad (patch) | |
tree | d237d86a7bc3437489986c2f6398f9b74f6e8096 /geo-replication | |
parent | fa29170d768e77c6bedf220f09fe90aa1819cc99 (diff) |
geo-rep: Fix data sync issue during hardlink, rename
Problem:
The data is not getting synced if master witnessed
IO as below.
1. echo "test_data" > f1
2. ln f1 f2
3. mv f2 f3
4. unlink f1
On master, 'f3' exists with data "test_data" but on
slave, only f3 exists with zero byte file without
backend gfid link.
Cause:
On master, since 'f2' no longer exists, the hardlink
is skipped during processing. Later, on trying to sync
rename, since source ('f2') doesn't exist, dst ('f3')
is created with same gfid. But in this use case, it
succeeds but backend gfid would not have linked as 'f1'
exists with the same gfid. So, rsync would fail with
ENOENT as backend gfid is not linked with 'f3' and 'f1'
is unlinked.
Fix:
On processing rename, if src doesn't exist on slave,
don't blindly create dst with same gfid. The gfid
needs to be checked, if it exists, hardlink needs
to be created instead of mknod.
Thanks Aravinda for helping in RCA :)
Change-Id: I5af4f99798ed1bcb297598a4bc796b701d1e0130
Signed-off-by: Kotresh HR <khiremat@redhat.com>
BUG: 1512483
Reporter: dimitri.ars@gmail.com
Diffstat (limited to 'geo-replication')
-rw-r--r-- | geo-replication/syncdaemon/resource.py | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/geo-replication/syncdaemon/resource.py b/geo-replication/syncdaemon/resource.py index a9810ae325b..c617c7b312e 100644 --- a/geo-replication/syncdaemon/resource.py +++ b/geo-replication/syncdaemon/resource.py @@ -688,8 +688,17 @@ class Server(object): elif not matching_disk_gfid(gfid, en): collect_failure(e, EEXIST, True) else: - (pg, bname) = entry2pb(en) - blob = entry_pack_reg_stat(gfid, bname, e['stat']) + slink = os.path.join(pfx, gfid) + st = lstat(slink) + # don't create multiple entries with same gfid + if isinstance(st, int): + (pg, bname) = entry2pb(en) + blob = entry_pack_reg_stat(gfid, bname, + e['stat']) + else: + cmd_ret = errno_wrap(os.link, [slink, en], + [ENOENT, EEXIST], [ESTALE]) + collect_failure(e, cmd_ret) else: st1 = lstat(en) if isinstance(st1, int): |