Find where your data is replicated, win a Percona Live ticket

Percona Live London starts on Monday, so this is the last in the series of free-Percona-Live tickets we’ll give away. But first — have you ever wondered what servers are in your MySQL replication hierarchy?

We have, too. As consultants, a lot of times we need to get a quick overview of the whole replication hierarchy and specific things about it, such as replication filters, versions, whether replication is running, how far behind it is, and so on. These things are very important for making sure that we don’t break something in the system, get blamed for breaking replication when it was already broken, and so on.

So we built pt-slave-find (it was actually born as mk-slave-find, ages ago before I even worked at Percona). It automatically detects and connects to every server in the replication hierarchy, and prints out a summary of each one’s most important details.

Here’s an example. Notice how one of the servers has a replication filter on it, the servers don’t all have the same version installed, and some are in the AWS cloud. All of these things are important to know — if we run a checksum on the non-cloud servers, for example, we could make the cloud servers fall far behind in replication.

$ perl pt-slave-find localhost
localhost
Version         5.1.57-rel12.8-log
Server ID       6275
Uptime          10+01:18:10 (started 2011-10-08T19:22:04)
Replication     Is a slave, has 5 slaves connected, is not read_only
Filters
Binary logging  MIXED
Slave status    0 seconds behind, running, no errors
Slave mode      IDEMPOTENT
Auto-increment  increment 4, offset 2
InnoDB version  1.0.16-12.8
+- 10.124.62.76
   Version         5.1.57-rel12.8-log
   Server ID       6276
   Uptime          12+03:35:17 (started 2011-10-06T17:04:57)
   Replication     Is a slave, has 2 slaves connected, is read_only
   Filters
   Binary logging  MIXED
   Slave status    0 seconds behind, running, no errors
   Slave mode      IDEMPOTENT
   Auto-increment  increment 4, offset 2
   InnoDB version  1.0.16-12.8
   +- 10.124.62.78
      Version         5.1.57-rel12.8-log
      Server ID       6278
      Uptime          12+03:53:59 (started 2011-10-06T16:46:15)
      Replication     Is a slave, has 0 slaves connected, is read_only
      Filters
      Binary logging  MIXED
      Slave status    0 seconds behind, running, no errors
      Slave mode      IDEMPOTENT
      Auto-increment  increment 4, offset 2
      InnoDB version  1.0.16-12.8
+- 10.124.62.77
   Version         5.1.57-rel12.8-log
   Server ID       6277
   Uptime          12+04:00:24 (started 2011-10-06T16:39:50)
   Replication     Is a slave, has 0 slaves connected, is read_only
   Filters
   Binary logging  MIXED
   Slave status    0 seconds behind, running, no errors
   Slave mode      IDEMPOTENT
   Auto-increment  increment 4, offset 2
   InnoDB version  1.0.16-12.8
+- 10.124.62.86
   Version         5.1.57-rel12.8-log
   Server ID       6286
   Uptime          12+02:52:15 (started 2011-10-06T17:47:59)
   Replication     Is a slave, has 4 slaves connected, is not read_only
   Filters
   Binary logging  MIXED
   Slave status    0 seconds behind, running, no errors
   Slave mode      STRICT
   Auto-increment  increment 1, offset 1
   InnoDB version  1.0.16-12.8
   +- [redacted].compute-1.amazonaws.com
      Version         5.1.43-60.hardy.7-log
      Server ID       3141592
      Uptime          11:29:58 (started 2011-10-18T09:10:16)
      Replication     Is a slave, has 0 slaves connected, is not read_only
      Filters         replicate_wild_ignore_table=foo%.mount%
      Binary logging  ROW
      Slave status    0 seconds behind, running, no errors
      Slave mode      STRICT
      Auto-increment  increment 1, offset 1
      InnoDB version  1.0.6-unknown
   +- [redacted].compute-1.amazonaws.com
      Version         5.1.43-60.hardy.7-log
      Server ID       19924124
      Uptime          12+23:32:10 (started 2011-10-05T21:08:04)
      Replication     Is a slave, has 1 slaves connected, is not read_only
      Filters
      Binary logging  STATEMENT
      Slave status    0 seconds behind, running, no errors
      Slave mode      STRICT
      Auto-increment  increment 1, offset 1
      InnoDB version  1.0.6-unknown
   +- [redacted].compute-1.amazonaws.com
      Version         5.1.43-60.hardy.7-log
      Server ID       207
      Uptime          12+23:40:41 (started 2011-10-05T20:59:34)
      Replication     Is a slave, has 1 slaves connected, is not read_only
      Filters
      Binary logging  STATEMENT
      Slave status    0 seconds behind, running, no errors
      Slave mode      STRICT
      Auto-increment  increment 1, offset 1
      InnoDB version  1.0.6-unknown
   +- [redacted].compute-1.amazonaws.com
      Version         5.1.43-60.hardy.7-log
      Server ID       330612
      Uptime          12+23:44:28 (started 2011-10-05T20:55:47)
      Replication     Is a slave, has 0 slaves connected, is not read_only
      Filters
      Binary logging  STATEMENT
      Slave status    0 seconds behind, running, no errors
      Slave mode      STRICT
      Auto-increment  increment 1, offset 1
      InnoDB version  1.0.6-unknown
+- [redacted].compute-1.amazonaws.com
   Version         5.1.43-60.hardy.7-log
   Server ID       215924
   Uptime          12+08:15:08 (started 2011-10-06T12:25:08)
   Replication     Is a slave, has 6 slaves connected, is read_only
   Filters
   Binary logging  MIXED
   Slave status    0 seconds behind, running, no errors
   Slave mode      IDEMPOTENT
   Auto-increment  increment 4, offset 3
   InnoDB version  1.0.6-unknown
+- 10.153.116.5
   Version         5.1.57-rel12.8-log
   Server ID       1165
   Uptime          20+09:44:46 (started 2011-09-28T10:55:30)
   Replication     Is a slave, has 0 slaves connected, is read_only
   Filters
   Binary logging  MIXED
   Slave status    0 seconds behind, running, no errors
   Slave mode      STRICT
   Auto-increment  increment 4, offset 3
   InnoDB version  1.0.16-12.8

So that’s how you can quickly find out what’s in your replication hierarchy, how it’s configured, and a few basic bits of status information.

Now how do you win a free ticket to Percona Live London? Watch our @percona Twitter stream to find out!