Geo-replication has a large number of repeated imports as shown below:
```
from syncdutils import set_term_handler, finalize, lf
from syncdutils import log_raise_exception, FreeObject, escape
```

There imports can be clubbed together as shown below:
``
from syncdutils import (set_term_handler, finalize, lf,
                        log_raise_exception, FreeObject, escape)
```

Fixes: #1105
Change-Id: I59a48dd57a70fc851d93150b85e736ce41e8b793
Signed-off-by: kshithijiyer <kshithij.ki@gmail.com>

With this patch now you can notice log if it is due to EIO:

[2020-03-16 16:24:48.293837] E [syncdutils(worker /bricks/brick1/mbr3):348:log_raise_exception] <top>: Getting "Input/Output error" is most likely due to a. Brick is down or b. Split brain issue.
[2020-03-16 16:24:48.293915] E [syncdutils(worker /bricks/brick1/mbr3):352:log_raise_exception] <top>: This is expected as per design to keep the consistency of the file system. Once the above issue is resolved geo-rep would automatically proceed further.

Change-Id: Ie33f2440bc96089731ce12afa8dab91d9550a7ca
Fixes: #1104
Signed-off-by: Sunny Kumar <sunkumar@redhat.com>

problem: Geo-rep gsyncd process mounts the master and slave volume
         on master nodes and slave nodes respectively and starts
         the sync. But it doesn't wait for the mount to be in ready
         state to accept I/O. The gluster mount is considered to be
         ready when all the distribute sub-volumes is up. If the all
         the distribute subvolumes are not up, it can cause ENOTCONN
         error, when lookup on file comes and file is on the subvol
         that is down.

solution: Added a Virtual Xattr "dht.subvol.status" which returns "1"
          if all subvols are up and "0" if all subvols are not up.
          Geo-rep then uses this virtual xattr after a fresh mount, to
          check whether all subvols are up or not and then starts the
          I/O.

fixes: bz#1664335
Change-Id: If3ad01d728b1372da7c08ccbe75a45bdc1ab2a91
Signed-off-by: Harpreet Kaur <hlalwani@redhat.com>
Signed-off-by: Kotresh HR <khiremat@redhat.com>

If non-standard ssh-port is used, Geo-rep can be configured to use ssh port
by using config option, the value should be in allowed port range and non negative.

At present it can accept negative value and outside allowed port range which is incorrect.

Many Linux kernels use the port range 32768 to 61000.
IANA suggests it should be in the range 1 to 2^16 - 1, so keeping the same.

$ gluster volume geo-replication master 127.0.0.1::slave config ssh-port -22
geo-replication config updated successfully
$ gluster volume geo-replication master 127.0.0.1::slave config ssh-port 22222222
geo-replication config updated successfully

This patch fixes the above issue and have added few validations around this
in test cases.

Change-Id: I9875ab3f00d7257370fbac6f5ed4356d2fed3f3c
Fixes: bz#1792276
Signed-off-by: Sunny Kumar <sunkumar@redhat.com>

There exists a window of 15 sec, where the deletes are picked up
by history crawl when the ignore_deletes is set to true.
And it eventually deletes the file/s from slave which is/are not
supposed to be deleted. Though it is working as per design, a
note regarding this is needed.

Added a warning message indicating the same.
Also logged info when the worker restarts after ignore-deletes
option set.

fixes: bz#1708603
Change-Id: I103be882fac18b4cef935efa355f5037a396f7c1
Signed-off-by: Shwetha K Acharya <sacharya@redhat.com>

When gsyncd failed with tracebacks during start, it prints
only exception object but not the error string. This patch
adds the error string as well.

Earlier:
"failed with ImportError"

Now:
"failed with ImportError: No module named _io."

fixes: bz#1771895
Change-Id: I0d772a250d4c2010a0c35053aa7b165b71f8434e
Signed-off-by: Kotresh HR <khiremat@redhat.com>

Geo-rep fails to start on python2 only machine like
centos6. It fails with "ImportError no module named _io".
This patch fixes the same.

fixes: bz#1771577
Change-Id: I8228458a853a230546f9faf29a0e9e0f23b3efec
Signed-off-by: Kotresh HR <khiremat@redhat.com>

- libgfchangelog is simplified by removing unnecessary API Class
- Merged Agent logic into Worker instead of running Worker and Agent as
  two separate processes and maintaining RPC between Worker and Agent.
- Geo-rep command Pause and Resume will continue without any changes.
  But Agent functionality also gets paused with that.

Updates: #755
Change-Id: Ie2c00fa7dddf21f180f0649e0aaf084d29023c98
Signed-off-by: Aravinda VK <avishwan@redhat.com>

Problem:
While syncing rename of directory in hybrid crawl, geo-rep
crashes as below.

Traceback (most recent call last):
  File "/usr/local/libexec/glusterfs/python/syncdaemon/repce.py", line 118, in worker
    res = getattr(self.obj, rmeth)(*in_data[2:])
  File "/usr/local/libexec/glusterfs/python/syncdaemon/resource.py", line 588, in entry_ops
    src_entry = get_slv_dir_path(slv_host, slv_volume, gfid)
  File "/usr/local/libexec/glusterfs/python/syncdaemon/syncdutils.py", line 687, in get_slv_dir_path
    [ENOENT], [ESTALE])
  File "/usr/local/libexec/glusterfs/python/syncdaemon/syncdutils.py", line 546, in errno_wrap
    return call(*arg)
PermissionError: [Errno 13] Permission denied: '/bricks/brick1/b1/.glusterfs/8e/c0/8ec0fcd4-d50f-4a6e-b473-a7943ab66640'

Cause:
Conversion of gfid to path for a directory uses readlink on backend
.glusterfs gfid path. But this fails for non root user with
permission denied.

Fix:
Use gfid2path interface to get the path from gfid

Change-Id: I9d40c713a1b32cea95144cbc0f384ada82972222
fixes: bz#1763439
Signed-off-by: Kotresh HR <khiremat@redhat.com>

After upgrade, if the config files are of old format, it
gets migrated to new format. Monitor process migrates it.
Since monitor doesn't run on nodes where bricks are not
hosted, it doesn't get migrated there. So this patch fixes
the config upgrade on nodes which doesn't host bricks.
This happens during config either on get/set/reset.

Change-Id: Ibade2f2310b0f3affea21a3baa1ae0eb71162cba
Signed-off-by: Kotresh HR <khiremat@redhat.com>
fixes: bz#1762220