openstack team mailing list archive

[Balamurugan V G <balamuruganvg@xxxxxxxxx>]

Hi,

I am exploring setting up a SWIFT Object Store across two data
centers. Lets say I have DC-A and DC-B. I have setup a swift-proxy and
two swift-storage nodes in DC-A. And I have setup one storage node in
DC-B. This is just an experimental setup and if this works well, will
have more storage nodes and proxy nodes in each DC. I have added the
storage nodes in DC-A in Zone1 and Zone2. And storage nodes in DC-B is
in Zone3. The replication count has been set to 3. My goal is to setup
a multi site OpenStack and I am exploring using SWIFT to store the
images such that the images can be shared across the DCs.

Here are my questions:

   1. There seems to be a concept of regions. How do I use that with
SWIFT in this case. I cant find any good documentation on it.
   2. In my current setup explained above, I can see that the
partitions are getting copied(and synced) fine between the nodes in
DC-A as confirmed by the used size returned by 'df -h /srv/node/sdb1'
(I know its crube but its good enough). I see that the node in DC-B
behaves differently. I see that the partitions are copied to this node
and then removed again continuously. It never settles. That is for
example, if I have a 5G content stored in the system, the DC-A nodes
shows that 5Gb is used. But the DC-B node shows that it increases to
5Gb and it then drops again to say 2Gb and then again increases to 5gb
and then drop again and so forth.The rsyncd logs shows few errors as
shown below:

2013/06/17 04:38:54 [6965] receiving file list
2013/06/17 04:53:52 [6963] rsync: connection unexpectedly closed
(731405377 bytes received so far) [receiver]
2013/06/17 04:53:52 [6963] rsync error: error in rsync protocol data
stream (code 12) at io.c(605) [receiver=3.0.9]
2013/06/17 04:53:52 [6963] rsync: connection unexpectedly closed (87
bytes received so far) [generator]
2013/06/17 04:53:52 [6963] rsync error: error in rsync protocol data
stream (code 12) at io.c(605) [generator=3.0.9]
2013/06/17 04:53:54 [6965] rsync: connection unexpectedly closed
(716563202 bytes received so far) [receiver]
2013/06/17 04:53:54 [6965] rsync error: error in rsync protocol data
stream (code 12) at io.c(605) [receiver=3.0.9]
2013/06/17 04:53:54 [6965] rsync: connection unexpectedly closed (87
bytes received so far) [generator]
2013/06/17 04:53:54 [6965] rsync error: error in rsync protocol data
stream (code 12) at io.c(605) [generator=3.0.9]
2013/06/16 21:54:24 [6996] name lookup failed for 10.5.64.47:
Temporary failure in name resolution
2013/06/16 21:54:24 [6996] connect from UNKNOWN (10.5.64.47)
2013/06/16 21:54:24 [6997] name lookup failed for 10.5.64.48:
Temporary failure in name resolution
2013/06/16 21:54:24 [6997] connect from UNKNOWN (10.5.64.48)
2013/06/17 04:54:25 [6996] rsync to object/sdb1/objects/189659 from
UNKNOWN (10.5.64.47)
2013/06/17 04:54:25 [6996] receiving file list
2013/06/17 04:54:25 [6997] rsync to object/sdb1/objects/189659 from
UNKNOWN (10.5.64.48)
2013/06/17 04:54:25 [6997] receiving file list

    I even tried to increase the timeout value of rsync from default
30sec to 600 sec but I still see the same issue. What could be wrong
here?


Any help will be greatly appreciated. Also any pointers to good
documentation on how to setup a multi site OpenStack deployment will
be very helpful. I see that there is good documentation to getup and
runing with a single or 3 nodes OpenStack setup, there is not much to
know how to deploy a large scale multi site OpenStack deployment :-(

Regards,
Balu