Bug 1614971

Description of problem:

The 4.0 RHV-H is not having glusterfs-server installed. So the file "/usr/libexec/glusterfs/glusterfind/S57glusterfind-delete-post.py" doesn't exist in 4.0 which come from this package.

While upgrading from 4.0 to 4.2, we will sync items present in the new 4.2 /var/ to the existing /var/ filesystem. Since "/var/lib/glustersd" directory is not present in the existing var filesystem, it will be synced.

===
2018-08-10 19:53:18,391 [DEBUG] (migrate_var) Copying /tmp/mnt.6fSmc//var/lib/glusterd to /var/lib/glusterd
===

We have symlink "/var/lib/glusterd/hooks/1/delete/post/S57glusterfind-delete-post" which points to "/usr/libexec/glusterfs/glusterfind/S57glusterfind-delete-post.py" under this directory. Since file S57glusterfind-delete-post.py doesn't exist in the 4.0 server, this symlink will be a often/broken.

===
[root@ ~]# imgbase w
[INFO] You are on rhvh-4.0-0.20170104.0+1

[root@ ~]# mount /dev/rhvh/rhvh-4.2.5.1-0.20180801.0+1 /tmp/rhvh-4.2
[root@ ~]# cd /tmp/rhvh-4.2
[root@ rhvh-4.2]# ls -l var/lib/glusterd/hooks/1/delete/post/S57glusterfind-delete-post
lrwxrwxrwx. 1 root root 64 Aug  1 14:05 var/lib/glusterd/hooks/1/delete/post/S57glusterfind-delete-post -> /usr/libexec/glusterfs/glusterfind/S57glusterfind-delete-post.py

rhvh-4.2]# python
Python 2.7.5 (default, Aug  2 2016, 04:20:16) 
[GCC 4.8.5 20150623 (Red Hat 4.8.5-4)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import os
>>> os.path.exists("/tmp/rhvh-4.2/var/lib/glusterd/hooks/1/delete/post/S57glusterfind-delete-post")
False
====

As per https://gerrit.ovirt.org/#/c/92376/, we are syncing files as well after syncing the directory. Although the link 
"/var/lib/glusterd/hooks/1/delete/post/S57glusterfind-delete-post" is already copied to existing /var/ as a part of "directory" sync, the imgbased will try to sync it again since it will fail the "os.path.exists" check as it's a broken link. This copy will fail with "No such file or directory:" since source file doesn't exist.


===
2018-08-10 19:53:18,601 [DEBUG] (migrate_var) Copying /tmp/mnt.6fSmc//var/lib/glusterd/hooks/1/delete/post/S57glusterfind-delete-post to /var/lib/glusterd/hooks/1/delete/post/S57glusterfind-delete-post

2018-08-10 19:53:29,742 [DEBUG] (MainThread) Traceback (most recent call last):
  File "/tmp/tmp.ybG3syJOJ9/usr/lib/python2.7/site-packages/imgbased/utils.py", line 1491, in run
    self._function(*self._args, **self._kwargs)
  File "/tmp/tmp.ybG3syJOJ9/usr/lib/python2.7/site-packages/imgbased/plugins/osupdater.py", line 245, in migrate_var
    shutil.copy2(newlv_path, realpath)
  File "/usr/lib64/python2.7/shutil.py", line 130, in copy2
    copyfile(src, dst)
  File "/usr/lib64/python2.7/shutil.py", line 82, in copyfile
    with open(src, 'rb') as fsrc:
IOError: [Errno 2] No such file or directory: u'/tmp/mnt.6fSmc//var/lib/glusterd/hooks/1/delete/post/S57glusterfind-delete-post'
====

Hence the upgrade will fail.


Version-Release number of selected component (if applicable):

imgbased-1.0.22

How reproducible:

100%

Steps to Reproduce:

Upgrade RHV-H 4.0 directly to 4.2.

Actual results:

The upgrade is failing during "var" migration

Expected results:

The upgrade should work fine.

Additional info: