0
  • I am building a MariaDB Galera Cluster, on AWS, EC2. Using MariaDB 10.5 and Galera 4.
  • I have two nodes in the California region, named galera_ca and galera_ca2, and a third node in Oregon name galera_or
  • The security groups between the servers are wide open, and the ping time between OR and CA is 12ms
  • I started galera_ca using galera_new_cluster
  • I started galera_ca2 using systemctl start mariadb

The two California nodes connect and share data just fine.
wsrep_cluster_size indicates that I have two nodes in the cluster.

  • I started galera_or using systemctl start mariadb

Oregon then hangs on starting for a very long time, and wsrep_cluster_size shows three nodes, but the server cannot be connected to.

Eventually systemctl start mariadb returns this message:
Job for mariadb.service failed because a fatal signal was delivered to the control process. See "systemctl status mariadb.service" and "journalctl -xe" for details.

systemctl status mariadb.service doesn't show anything exceptional,

journalctl -xe shows:
requested state transfer from 'any', but it is impossible to select State Transfer donor: Resource temporarily unavailable

wsrep_cluster_size still shows three nodes, but mariadb is not running in OR.
If I try to shut down either of the California servers systemctl stop mariadb it never returns.

All three servers have basically the same configuration:

[galera]
wsrep_on=ON
wsrep_provider=/usr/lib64/galera-4/libgalera_smm.so

wsrep_node_name='galera_ca'
wsrep_node_address="INTERNAL ADDRESS OF THIS NODE"

wsrep_cluster_name='galera-experiment'
wsrep_cluster_address="gcomm://EXTERNAL ADDRESS OF NODE CA, EXTERNAL ADDRESS OF NODE CA2, EXTERNAL ADDRESS OF NODE OR"

wsrep_provider_options="gcache.size=300M; gcache.page_size=300M"
wsrep_slave_threads=4
wsrep_sst_method=rsync

binlog_format=row
default_storage_engine=InnoDB
innodb_autoinc_lock_mode=2
bind-address=0.0.0.0

If I try just one CA node and the OR node, the result is the same.

2
  • AWS does a lot to obviate the need for Galera. However, I do not have enough details to make that case.
    – Rick James
    Dec 9, 2020 at 17:34
  • That's not true, AWS does not provide cross-region read/write cluster Dec 10, 2020 at 16:12

1 Answer 1

0

In wsrep_node_address on Amazon EC2, you must use the global DNS name, instead of the internal IP address.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.