daz bdb856c8fe [docs] Migrate ops and appendix content
1. Migrate Ops chapter and tips and tricks appendix to developer docs
2. Migrate Appendix G to a chapter in the developer docs
3. Minor edits

Change-Id: I4070f02b75a8f9614545be0744e63ba76a3b49e2
Implements: blueprint osa-install-guide-overhaul
2016-06-17 10:13:27 +10:00

94 lines
3.2 KiB
ReStructuredText

`Home <index.html>`_ OpenStack-Ansible Installation Guide
==================
Starting a cluster
==================
Gracefully shutting down all nodes destroys the cluster. Starting or
restarting a cluster from zero nodes requires creating a new cluster on
one of the nodes.
#. Start a new cluster on the most advanced node.
Check the ``seqno`` value in the ``grastate.dat`` file on all of the nodes:
.. code-block:: shell-session
# ansible galera_container -m shell -a "cat /var/lib/mysql/grastate.dat"
node2_galera_container-49a47d25 | success | rc=0 >>
# GALERA saved state version: 2.1
uuid: 338b06b0-2948-11e4-9d06-bef42f6c52f1
seqno: 31
cert_index:
node3_galera_container-3ea2cbd3 | success | rc=0 >>
# GALERA saved state version: 2.1
uuid: 338b06b0-2948-11e4-9d06-bef42f6c52f1
seqno: 31
cert_index:
node4_galera_container-76275635 | success | rc=0 >>
# GALERA saved state version: 2.1
uuid: 338b06b0-2948-11e4-9d06-bef42f6c52f1
seqno: 31
cert_index:
In this example, all nodes in the cluster contain the same positive
``seqno`` values as they were synchronized just prior to
graceful shutdown. If all ``seqno`` values are equal, any node can
start the new cluster.
.. code-block:: shell-session
# /etc/init.d/mysql start --wsrep-new-cluster
This command results in a cluster containing a single node. The
``wsrep_cluster_size`` value shows the number of nodes in the
cluster.
.. code-block:: shell-session
node2_galera_container-49a47d25 | FAILED | rc=1 >>
ERROR 2002 (HY000): Can't connect to local MySQL server
through socket '/var/run/mysqld/mysqld.sock' (111)
node3_galera_container-3ea2cbd3 | FAILED | rc=1 >>
ERROR 2002 (HY000): Can't connect to local MySQL server
through socket '/var/run/mysqld/mysqld.sock' (2)
node4_galera_container-76275635 | success | rc=0 >>
Variable_name Value
wsrep_cluster_conf_id 1
wsrep_cluster_size 1
wsrep_cluster_state_uuid 338b06b0-2948-11e4-9d06-bef42f6c52f1
wsrep_cluster_status Primary
#. Restart MariaDB on the other nodes and verify that they rejoin the
cluster.
.. code-block:: shell-session
node2_galera_container-49a47d25 | success | rc=0 >>
Variable_name Value
wsrep_cluster_conf_id 3
wsrep_cluster_size 3
wsrep_cluster_state_uuid 338b06b0-2948-11e4-9d06-bef42f6c52f1
wsrep_cluster_status Primary
node3_galera_container-3ea2cbd3 | success | rc=0 >>
Variable_name Value
wsrep_cluster_conf_id 3
wsrep_cluster_size 3
wsrep_cluster_state_uuid 338b06b0-2948-11e4-9d06-bef42f6c52f1
wsrep_cluster_status Primary
node4_galera_container-76275635 | success | rc=0 >>
Variable_name Value
wsrep_cluster_conf_id 3
wsrep_cluster_size 3
wsrep_cluster_state_uuid 338b06b0-2948-11e4-9d06-bef42f6c52f1
wsrep_cluster_status Primary
--------------
.. include:: navigation.txt