Active Standby Nodes on Community Edition?

paulc

Hello.

Can someone tell me if I can deploy an Active Standby Node with community edition? I am planning a new 8.1 install (upgrading from 7.0) and I would like to use this feature.

Thanks.
Paulc

paulc

I should clarify - 3 node cluster, so the active standby would be the 4th.

Thanks.

drlove

Vertica Community Edition license has a 3-node limit so as long as you only have 3 nodes up and running at a time it should work.

paulc

Great, thanks.

Jim_Knicely

From my understanding, when using a Vertica CE licence, admintools will not let you create a database on more than three nodes, or add a node to a database that already has 3 nodes.

So, if you try to create a database on 4 nodes, you get this error:

Desired database node count (4) exceeds license max node count (3)

If you try to add a 4th node, you'll get this error:

ROLLBACK 2382: Cannot create another node. The current license permits 3 node(s) and the database catalog already contains 3 node(s)

What if 2 nodes are up and one is down and already a stand by?

[dbadmin@localhost ~]$ vsql -c "select node_name, node_state, node_type from nodes order by node_name;"
    node_name     | node_state | node_type
------------------+------------+-----------
 v_test2_node0001 | UP         | PERMANENT
 v_test2_node0002 | UP         | PERMANENT
 v_test2_node0003 | DOWN       | STANDBY
(3 rows)

[dbadmin@localhost ~]$ admintools -t db_add_node -s 192.168.56.105 -d test2
                Verifying database connectivity...192.168.56.102
There was an error adding the nodes to the database
ROLLBACK 2382:  Cannot create another node. The current license permits 3 node(s) and the database catalog already contains 3 node(s)

Still can't create a cluster with > 3 nodes!

Basically, when using Vertica CE, SELECT * FROM nodes; must always return 3 or less nodes...

Besides, Vertica CE is not permitted for use in a production environment. What "real world" need is there for active stand by nodes in a test environment?

Jim_Knicely

@paulc - The point I was trying to make is that with Vertica CE you can not have a 3 node cluster with a 4th node acting as an active standby as that would technically be 4 nodes total in the cluster.

drlove

Thanks Jim, I couldn't test it so I shouldn't have guessed without testing it first.