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Re: Troubleshooting Swift 1.7.4 on mini servers

To: John Dickinson <me@xxxxxx>
From: Nathan Trueblood <nathan@xxxxxxxxxxxxxxxx>
Date: Mon, 29 Oct 2012 18:16:52 -0700
Cc: openstack@xxxxxxxxxxxxxxxxxxx
In-reply-to: <18530D13-24DA-4793-A8A7-7B849BE949AA@not.mn>
Still no further clues.   I re-created all the volumes I'm using for Swift.
 Plenty of Inodes free:

lab@data02:~$ df -i
Filesystem        Inodes IUsed     IFree IUse% Mounted on
/dev/sda2       12214272 39290  12174982    1% /
none              107979   482    107497    1% /dev
none              107979   268    107711    1% /run
none              107979     2    107977    1% /run/lock
none              107979     1    107978    1% /run/shm
/dev/sda1          49152    23     49129    1% /boot
/dev/sda4      134046400    37 134046363    1% /srv/node/sda4

I successfully upload a small object to container cont1, then cont2.   When
I upload to cont3, I see the following in the object-server log (data02)

This seems to be the problematic sequence:

Data02 has ip 192.168.1.202
Data03 has ip 192.168.1.203

1. First the account server reports an HTTP 201 on the container from a
different object server in a different zone.
2. Then the object server reports a 404 trying to HEAD the new object.
3. Then the object server reports a 507 trying to PUT the new object.

>From this point the operation eventually fails and the proxy reports a 503.

Oct 29 17:58:20 data02 account-server 192.168.1.203 - -
[30/Oct/2012:00:58:20 +0000] "PUT /sda4/116021/AUTH_system/cont3" 201 -
"tx5a3ca6c845af41928e0ba6b7bc58d2da" "-" "-" 0.0082 ""
Oct 29 17:58:20 data02 object-server 192.168.1.111 - -
[30/Oct/2012:00:58:20 +0000] "HEAD
/sda4/257613/AUTH_system/cont3/home/lab/bigfile3" 404 - "-"
"tx5f21503ff12e45e39a80eb52f6757261" "-" 0.0011
Oct 29 17:58:20 data02 object-server 192.168.1.111 - -
[30/Oct/2012:00:58:20 +0000] "PUT
/sda4/257613/AUTH_system/cont3/home/lab/bigfile3" 507 - "-"
"tx425494dc372740e28d043a07d3a08b9a" "-" 0.0031

In an earlier, successful transaction I noticed that between Steps 1 and 2
above, there is a response from the container-server:

Oct 29 17:57:59 data02 account-server 192.168.1.204 - -
[30/Oct/2012:00:57:59 +0000] "PUT /sda4/116021/AUTH_system/cont2" 201 -
"txb10d75886bf14e4eba14fcc52d81c5d9" "-" "-" 0.0182 ""
Oct 29 17:57:59 data02 container-server 192.168.1.111 - -
[30/Oct/2012:00:57:59 +0000] "PUT /sda4/122355/AUTH_system/cont2" 201 -
"txb10d75886bf14e4eba14fcc52d81c5d9" "-" "-" 0.1554
Oct 29 17:57:59 data02 object-server 192.168.1.111 - -
[30/Oct/2012:00:57:59 +0000] "HEAD
/sda4/226151/AUTH_system/cont2/home/lab/bigfile3" 404 - "-"
"tx1c514850530849d1bfbfa716d9039b87" "-" 0.0012
Oct 29 17:57:59 data02 container-server 192.168.1.204 - -
[30/Oct/2012:00:57:59 +0000] "PUT
/sda4/122355/AUTH_system/cont2/home/lab/bigfile3" 201 -
"tx8130af5cae484e5f9c5a25541d1c87aa" "-" "-" 0.0041
Oct 29 17:57:59 data02 object-server 192.168.1.111 - -
[30/Oct/2012:00:57:59 +0000] "PUT
/sda4/226151/AUTH_system/cont2/home/lab/bigfile3" 201 - "-"
"tx8130af5cae484e5f9c5a25541d1c87aa" "-" 0.1716


So maybe the container server is failing to create the new container?
Maybe a bug in auto-create of containers?

Definitely NOT a problem with the filesystem, but something is causing the
object-server to think there is a problem with the filesystem.

I suspect a bug in one of the underlying libraries.

Any further suggestions on how to troubleshoot?

Thanks.   When I finally find the solution, I'll post my results.

-N

On Fri, Oct 26, 2012 at 11:21 PM, John Dickinson <me@xxxxxx> wrote:

> A 507 is returned by the object servers in 2 situations: 1) the drives are
> full or 2) the drives have been unmounted because of disk error.
>
> It's highly likely that you simply have full drives. Remember that the
> usable space in your cluster is 1/N where N = replica count. As an example,
> with 3 replicas and 5 nodes with a single 1TB drive each, you only have
> about 1.6TB available for data.
>
> As Pete suggested in his response, how big are your drives, and what does
> `df` tell you?
>
> --John
>
>
> On Oct 26, 2012, at 5:26 PM, Nathan Trueblood <nathan@xxxxxxxxxxxxxxxx>
> wrote:
>
> > Hey folks-
> >
> > I'm trying to figure out what's going wrong with my Swift deployment on
> a small cluster of "mini" servers.   I have a small test cluster (5 storage
> nodes, 1 proxy) of mini-servers that are ARM-based.   The proxy is a
> regular, Intel-based server with plenty of RAM.   The
> object/account/container servers are relatively small, with 2GB of RAM per
> node.
> >
> > Everything starts up fine, but now I'm trying to troubleshoot a strange
> problem.   After I successfully upload a few test files, it seems like the
> storage system stops responding and the proxy gives me a 503 error.
> >
> > Here's the test sequence I run on my proxy:
> >
> > lab@proxy01:~/bin$ ./swiftcl.sh stat
> > swift -A http://proxy01:8080/auth/v1.0 -U system:root -K testpass stat
> >    Account: AUTH_system
> > Containers: 5
> >    Objects: 4
> >      Bytes: 47804968
> > Accept-Ranges: bytes
> > X-Timestamp: 1351294912.72119
> > lab@proxy01:~/bin$ ./swiftcl.sh upload myfiles1 /home/lab/bigfile1
> > swift -A http://proxy01:8080/auth/v1.0 -U system:root -K testpass
> upload myfiles1 /home/lab/bigfile1
> > home/lab/bigfile1
> > lab@proxy01:~/bin$ ./swiftcl.sh upload myfiles2 /home/lab/bigfile1
> > swift -A http://proxy01:8080/auth/v1.0 -U system:root -K testpass
> upload myfiles2 /home/lab/bigfile1
> > home/lab/bigfile1
> > lab@proxy01:~/bin$ ./swiftcl.sh upload myfiles3 /home/lab/bigfile1
> > swift -A http://proxy01:8080/auth/v1.0 -U system:root -K testpass
> upload myfiles3 /home/lab/bigfile1
> > home/lab/bigfile1
> > lab@proxy01:~/bin$ ./swiftcl.sh upload myfiles4 /home/lab/bigfile1
> > swift -A http://proxy01:8080/auth/v1.0 -U system:root -K testpass
> upload myfiles4 /home/lab/bigfile1
> > home/lab/bigfile1
> > lab@proxy01:~/bin$ ./swiftcl.sh upload myfiles5 /home/lab/bigfile1
> > swift -A http://proxy01:8080/auth/v1.0 -U system:root -K testpass
> upload myfiles5 /home/lab/bigfile1
> > Object PUT failed:
> http://172.16.1.111:8080/v1/AUTH_system/myfiles5/home/lab/bigfile1 503
> Service Unavailable  [first 60 chars of response] 503 Service Unavailable
> >
> > The server is currently unavailable
> > lab@proxy01:~/bin$ ./swiftcl.sh stat
> > swift -A http://proxy01:8080/auth/v1.0 -U system:root -K testpass stat
> >    Account: AUTH_system
> > Containers: 6
> >    Objects: 5
> >      Bytes: 59756210
> > Accept-Ranges: bytes
> > X-Timestamp: 1351294912.72119
> >
> > Here's the corresponding log on the Proxy:
> >
> > Oct 26 17:06:52 proxy01 proxy-server - 127.0.0.1 27/Oct/2012/00/06/52
> GET /auth/v1.0/ HTTP/1.0 200 - - - - - - - - 0.0010
> > Oct 26 17:07:13 proxy01 proxy-server - 127.0.0.1 27/Oct/2012/00/07/13
> GET /auth/v1.0/ HTTP/1.0 200 - - - - - - - - 0.0017
> > Oct 26 17:07:13 proxy01 proxy-server - 127.0.0.1 27/Oct/2012/00/07/13
> GET /auth/v1.0/ HTTP/1.0 200 - - - - - - - - 0.0016
> > Oct 26 17:07:22 proxy01 proxy-server - 127.0.0.1 27/Oct/2012/00/07/22
> GET /auth/v1.0/ HTTP/1.0 200 - - - - - - - - 0.0010
> > Oct 26 17:07:22 proxy01 proxy-server - 127.0.0.1 27/Oct/2012/00/07/22
> GET /auth/v1.0/ HTTP/1.0 200 - - - - - - - - 0.0016
> > Oct 26 17:07:27 proxy01 proxy-server - 127.0.0.1 27/Oct/2012/00/07/27
> GET /auth/v1.0/ HTTP/1.0 200 - - - - - - - - 0.0010
> > Oct 26 17:07:27 proxy01 proxy-server - 127.0.0.1 27/Oct/2012/00/07/27
> GET /auth/v1.0/ HTTP/1.0 200 - - - - - - - - 0.0016
> > Oct 26 17:07:27 proxy01 proxy-server Handoff requested (1) (txn:
> tx6946419daba54efe9c2878f8a2a78f88) (client_ip: 172.16.1.111)
> > Oct 26 17:07:27 proxy01 proxy-server Handoff requested (2) (txn:
> tx6946419daba54efe9c2878f8a2a78f88) (client_ip: 172.16.1.111)
> > Oct 26 17:07:33 proxy01 proxy-server - 127.0.0.1 27/Oct/2012/00/07/33
> GET /auth/v1.0/ HTTP/1.0 200 - - - - - - - - 0.0010
> > Oct 26 17:07:33 proxy01 proxy-server - 127.0.0.1 27/Oct/2012/00/07/33
> GET /auth/v1.0/ HTTP/1.0 200 - - - - - - - - 0.0016
> > Oct 26 17:07:33 proxy01 proxy-server Handoff requested (1) (txn:
> tx5f9659f74cb2491f9a63cbb84f680c5c) (client_ip: 172.16.1.111)
> > Oct 26 17:07:33 proxy01 proxy-server Handoff requested (2) (txn:
> tx5f9659f74cb2491f9a63cbb84f680c5c) (client_ip: 172.16.1.111)
> > Oct 26 17:07:39 proxy01 proxy-server - 127.0.0.1 27/Oct/2012/00/07/39
> GET /auth/v1.0/ HTTP/1.0 200 - - - - - - - - 0.0009
> > Oct 26 17:07:39 proxy01 proxy-server - 127.0.0.1 27/Oct/2012/00/07/39
> GET /auth/v1.0/ HTTP/1.0 200 - - - - - - - - 0.0009
> > Oct 26 17:07:39 proxy01 proxy-server Handoff requested (1) (txn:
> tx8dc917a4a8c84c40a4429b7bab0323c6) (client_ip: 172.16.1.111)
> > Oct 26 17:07:39 proxy01 proxy-server Handoff requested (2) (txn:
> tx8dc917a4a8c84c40a4429b7bab0323c6) (client_ip: 172.16.1.111)
> > Oct 26 17:07:40 proxy01 proxy-server Object PUT returning 503, 1/2
> required connections (txn: tx8dc917a4a8c84c40a4429b7bab0323c6) (client_ip:
> 172.16.1.111)
> > Oct 26 17:07:41 proxy01 proxy-server Object PUT returning 503, 1/2
> required connections (txn: tx07a1f5dfaa23445a88eaa4a2ade68466) (client_ip:
> 172.16.1.111)
> > Oct 26 17:07:43 proxy01 proxy-server Object PUT returning 503, 1/2
> required connections (txn: tx938d08b706844db3886695b798bd9fad) (client_ip:
> 172.16.1.111)
> > Oct 26 17:07:47 proxy01 proxy-server Object PUT returning 503, 1/2
> required connections (txn: txa35e9f8a54924f139e13d6f3a5dc457f) (client_ip:
> 172.16.1.111)
> > Oct 26 17:07:55 proxy01 proxy-server Object PUT returning 503, 1/2
> required connections (txn: txc2f5c35b54a14b32a2d0178423bc7771) (client_ip:
> 172.16.1.111)
> > Oct 26 17:08:11 proxy01 proxy-server Object PUT returning 503, 1/2
> required connections (txn: txd8df89e76edd40f3b4c04091b3cbc857) (client_ip:
> 172.16.1.111)
> > Oct 26 17:08:17 proxy01 proxy-server - 127.0.0.1 27/Oct/2012/00/08/17
> GET /auth/v1.0/ HTTP/1.0 200 - - - - - - - - 0.0011
> >
> > And here's the log from one of the Storage Nodes:
> >
> > Oct 26 17:07:20 data05 container-server 192.168.1.111 - -
> [27/Oct/2012:00:07:20 +0000] "PUT /sda6/200589/AUTH_system/myfiles1" 201 -
> "tx063cd0643ef64d169b3bc5a86a808df4" "-" "-" 0.0510
> > Oct 26 17:07:20 data05 account-server 192.168.1.204 - -
> [27/Oct/2012:00:07:20 +0000] "PUT /sda6/116021/AUTH_system/myfiles1" 201 -
> "tx063cd0643ef64d169b3bc5a86a808df4" "-" "-" 0.0154 ""
> > Oct 26 17:07:20 data05 object-server 192.168.1.111 - -
> [27/Oct/2012:00:07:20 +0000] "HEAD
> /sda6/36256/AUTH_system/myfiles1/home/lab/bigfile1" 404 - "-"
> "tx6f1018e5da4d4974a85d544a0874a581" "-" 0.0015
> > Oct 26 17:07:21 data05 object-server 192.168.1.111 - -
> [27/Oct/2012:00:07:21 +0000] "PUT
> /sda6/36256/AUTH_system/myfiles1/home/lab/bigfile1" 201 - "-"
> "tx59f931d3281d41159eba0e0c88c18107" "-" 1.0255
> > Oct 26 17:07:21 data05 container-server 192.168.1.202 - -
> [27/Oct/2012:00:07:21 +0000] "PUT
> /sda6/200589/AUTH_system/myfiles1/home/lab/bigfile1" 201 -
> "tx59f931d3281d41159eba0e0c88c18107" "-" "-" 0.0218
> > Oct 26 17:07:24 data05 account-replicator Beginning replication run
> > Oct 26 17:07:25 data05 account-replicator Replication run OVER
> > Oct 26 17:07:25 data05 account-replicator Attempted to replicate 1 dbs
> in 0.21688 seconds (4.61073/s)
> > Oct 26 17:07:25 data05 account-replicator Removed 0 dbs
> > Oct 26 17:07:25 data05 account-replicator 2 successes, 0 failures
> > Oct 26 17:07:25 data05 account-replicator no_change:0 ts_repl:0 diff:2
> rsync:0 diff_capped:0 hashmatch:0 empty:0
> > Oct 26 17:07:28 data05 account-server 192.168.1.204 - -
> [27/Oct/2012:00:07:28 +0000] "PUT /sda6/116021/AUTH_system/myfiles1" 201 -
> "-" "-" "-" 0.0021 ""
> > Oct 26 17:07:29 data05 account-server 192.168.1.205 - -
> [27/Oct/2012:00:07:29 +0000] "PUT /sda6/116021/AUTH_system/myfiles2" 201 -
> "txbace9f92a41a4645beb9159a802fc12d" "-" "-" 0.0178 ""
> > Oct 26 17:07:30 data05 object-server 192.168.1.111 - -
> [27/Oct/2012:00:07:30 +0000] "PUT
> /sda6/63086/AUTH_system/myfiles2/home/lab/bigfile1" 201 - "-"
> "txa4fac7ceab2948ae9010b4ce4cb56b97" "-" 0.7135
> > Oct 26 17:07:33 data05 object-replicator Starting object replication
> pass.
> > Oct 26 17:07:33 data05 object-replicator 4/4 (100.00%) partitions
> replicated in 0.17s (23.71/sec, 0s remaining)
> > Oct 26 17:07:33 data05 object-replicator 4 suffixes checked - 50.00%
> hashed, 0.00% synced
> > Oct 26 17:07:33 data05 object-replicator Partition times: max 0.1012s,
> min 0.0164s, med 0.0273s
> > Oct 26 17:07:33 data05 object-replicator Object replication complete.
> (0.00 minutes)
> > Oct 26 17:07:34 data05 account-server 192.168.1.206 - -
> [27/Oct/2012:00:07:34 +0000] "PUT /sda6/116021/AUTH_system/myfiles3" 201 -
> "txa547450c156d4df9ad7e42c04dcabd8f" "-" "-" 0.0168 ""
> > Oct 26 17:07:34 data05 container-server 192.168.1.111 - -
> [27/Oct/2012:00:07:34 +0000] "PUT /sda6/118594/AUTH_system/myfiles3" 202 -
> "txa547450c156d4df9ad7e42c04dcabd8f" "-" "-" 0.0399
> > Oct 26 17:07:35 data05 container-server 192.168.1.206 - -
> [27/Oct/2012:00:07:35 +0000] "PUT
> /sda6/118594/AUTH_system/myfiles3/home/lab/bigfile1" 201 -
> "tx6946419daba54efe9c2878f8a2a78f88" "-" "-" 0.0022
> > Oct 26 17:07:35 data05 object-server 192.168.1.111 - -
> [27/Oct/2012:00:07:35 +0000] "PUT
> /sda6/35436/AUTH_system/myfiles3/home/lab/bigfile1" 201 - "-"
> "tx6946419daba54efe9c2878f8a2a78f88" "-" 0.6806
> > Oct 26 17:07:36 data05 account-server 192.168.1.205 - -
> [27/Oct/2012:00:07:36 +0000] "PUT /sda6/116021/AUTH_system/myfiles2" 201 -
> "-" "-" "-" 0.0021 ""
> > Oct 26 17:07:37 data05 object-auditor Begin object audit "forever" mode
> (ZBF)
> > Oct 26 17:07:37 data05 object-auditor Object audit (ZBF) "forever" mode
> completed: 0.04s. Total quarantined: 0, Total errors: 0, Total files/sec:
> 89.46 , Total bytes/sec: 0.00, Auditing time: 0.04, Rate: 0.95
> > Oct 26 17:07:40 data05 account-server 192.168.1.204 - -
> [27/Oct/2012:00:07:40 +0000] "PUT /sda6/116021/AUTH_system/myfiles4" 201 -
> "txe095c94f8e5c4c4681a8d6a9c330bb7b" "-" "-" 0.0200 ""
> > Oct 26 17:07:40 data05 container-server 192.168.1.111 - -
> [27/Oct/2012:00:07:40 +0000] "PUT /sda6/217542/AUTH_system/myfiles4" 202 -
> "txe095c94f8e5c4c4681a8d6a9c330bb7b" "-" "-" 0.0671
> > Oct 26 17:07:40 data05 container-server 192.168.1.206 - -
> [27/Oct/2012:00:07:40 +0000] "PUT
> /sda6/217542/AUTH_system/myfiles4/home/lab/bigfile1" 201 -
> "tx5f9659f74cb2491f9a63cbb84f680c5c" "-" "-" 0.0023
> > Oct 26 17:07:40 data05 object-server 192.168.1.111 - -
> [27/Oct/2012:00:07:40 +0000] "PUT
> /sda6/49697/AUTH_system/myfiles4/home/lab/bigfile1" 201 - "-"
> "tx5f9659f74cb2491f9a63cbb84f680c5c" "-" 0.6038
> > Oct 26 17:07:44 data05 container-updater Begin container update sweep
> > Oct 26 17:07:44 data05 container-replicator Beginning replication run
> > Oct 26 17:07:44 data05 account-server 192.168.1.206 - -
> [27/Oct/2012:00:07:44 +0000] "PUT /sda6/116021/AUTH_system/myfiles1" 201 -
> "-" "-" "-" 0.0021 ""
> > Oct 26 17:07:44 data05 account-server 192.168.1.206 - -
> [27/Oct/2012:00:07:44 +0000] "PUT /sda6/116021/AUTH_system/myfiles3" 201 -
> "-" "-" "-" 0.0021 ""
> > Oct 26 17:07:44 data05 account-server 192.168.1.206 - -
> [27/Oct/2012:00:07:44 +0000] "PUT /sda6/116021/AUTH_system/myfiles4" 201 -
> "-" "-" "-" 0.0021 ""
> > Oct 26 17:07:45 data05 account-server 192.168.1.203 - -
> [27/Oct/2012:00:07:45 +0000] "PUT /sda6/116021/AUTH_system/myfiles2" 201 -
> "-" "-" "-" 0.0023 ""
> > Oct 26 17:07:45 data05 account-server 192.168.1.203 - -
> [27/Oct/2012:00:07:45 +0000] "PUT /sda6/116021/AUTH_system/myfiles1" 201 -
> "-" "-" "-" 0.0020 ""
> > Oct 26 17:07:45 data05 container-replicator Replication run OVER
> > Oct 26 17:07:45 data05 account-server 192.168.1.203 - -
> [27/Oct/2012:00:07:45 +0000] "PUT /sda6/116021/AUTH_system/myfiles3" 201 -
> "-" "-" "-" 0.0223 ""
> > Oct 26 17:07:45 data05 container-replicator Attempted to replicate 5 dbs
> in 0.83001 seconds (6.02399/s)
> > Oct 26 17:07:45 data05 container-replicator Removed 0 dbs
> > Oct 26 17:07:45 data05 container-replicator 10 successes, 0 failures
> > Oct 26 17:07:45 data05 container-replicator no_change:8 ts_repl:0 diff:2
> rsync:0 diff_capped:0 hashmatch:0 empty:0
> > Oct 26 17:07:45 data05 container-updater Container update sweep
> completed: 0.98s
> > Oct 26 17:07:46 data05 account-server 192.168.1.205 - -
> [27/Oct/2012:00:07:46 +0000] "PUT /sda6/116021/AUTH_system/myfiles5" 201 -
> "tx7ba0264da03c485ca3c3b4048f6a3d8c" "-" "-" 0.0098 ""
> > Oct 26 17:07:46 data05 container-server 192.168.1.111 - -
> [27/Oct/2012:00:07:46 +0000] "PUT /sda6/122255/AUTH_system/myfiles5" 202 -
> "tx7ba0264da03c485ca3c3b4048f6a3d8c" "-" "-" 0.0465
> > Oct 26 17:07:46 data05 object-server 192.168.1.111 - -
> [27/Oct/2012:00:07:46 +0000] "HEAD
> /sda6/150861/AUTH_system/myfiles5/home/lab/bigfile1" 404 - "-"
> "txf08e8b91b2894a9da099f26b5300327b" "-" 0.0011
> > Oct 26 17:07:46 data05 object-server 192.168.1.111 - -
> [27/Oct/2012:00:07:46 +0000] "PUT
> /sda6/150861/AUTH_system/myfiles5/home/lab/bigfile1" 507 - "-"
> "tx8dc917a4a8c84c40a4429b7bab0323c6" "-" 0.0031
> >
> > Right now, there is nothing special in the object-server.conf:
> >
> > [DEFAULT]
> > bind_ip = 192.168.1.206
> > workers = 1
> >
> > [pipeline:main]
> > pipeline = object-server
> >
> > [app:object-server]
> > use = egg:swift#object
> >
> > [object-replicator]
> >
> > [object-updater]
> >
> > [object-auditor]
> >
> > [object-server]
> > set log_level = DEBUG
> >
> > My general question is: how do I troubleshoot this?   I've tried turning
> on debug logging on the Object Server, but I don't get any additional clues.
> >
> > The Object-servers do give a 507 error, which might indicate a disk
> problem, but there is nothing wrong with the storage drive.   And also if
> there was a fundamental drive problem then I wouldn't be able to upload
> objects in the first place.
> >
> > My best guess at the moment is that I should adjust the configuration of
> the object servers to reflect their lower performance.   What would I
> adjust, the cache size?   I'm not seeing any log messages that would
> indicate a time-out.
> >
> > Thanks in advance for your advice.
> >
> > -N
> > _______________________________________________
> > Mailing list: https://launchpad.net/~openstack
> > Post to     : openstack@xxxxxxxxxxxxxxxxxxx
> > Unsubscribe : https://launchpad.net/~openstack
> > More help   : https://help.launchpad.net/ListHelp
>
>
Follow ups

Re: Troubleshooting Swift 1.7.4 on mini servers
From: Pete Zaitcev, 2012-10-30
Re: Troubleshooting Swift 1.7.4 on mini servers
From: Alex Yang, 2012-10-30
References

Troubleshooting Swift 1.7.4 on mini servers
From: Nathan Trueblood, 2012-10-27
Re: Troubleshooting Swift 1.7.4 on mini servers
From: John Dickinson, 2012-10-27