Re: 3 nodes / host cluster - Nicolas Olivier - com.mysql.lists.cluster

4 messages in com.mysql.lists.clusterRe: 3 nodes / host cluster

From	Sent On	Attachments
Nicolas Olivier	17 Jun 2005 03:01
Mikael Ronström	17 Jun 2005 05:10
Nicolas Olivier	17 Jun 2005 05:37
Nicolas Olivier	17 Jun 2005 08:07

Subject:	Re: 3 nodes / host cluster
From:	Nicolas Olivier (noli...@alphalink.fr)
Date:	06/17/2005 08:07:38 AM
List:	com.mysql.lists.cluster

Well, in fact it works, seems to be a misunderstanding of the output...

Well, I've updated my config.ini in order to get them identical. So they are the same as previously, I just added:

On hostB:

[ndb_mgmd] Id=1 HostName= hostA

On hostA:

[ndb_mgmd] Id=2 HostName= hostB

The 2 ndb_mgmd start correctly (still on hostA first then on hostB), but I when
connect them with the management client, things look like a bit messy.

On hostA:

ndb_mgm> show Cluster Configuration

--------------------- [ndbd(NDB)] 2 node(s) id=3 (not connected, accepting connect from hostA) id=4 (not connected, accepting connect from hostB)

[ndb_mgmd(MGM)] 2 node(s) id=1 @hostB (Version: 4.1.11) id=2 (not connected, accepting connect from hostB)

[mysqld(API)] 2 node(s) id=5 (not connected, accepting connect from any host) id=6 (not connected, accepting connect from any host)

ndb_mgm> 1 status Node 1: not connected

ndb_mgm> 2 status Node 2: not connected

On hostB:

ndb_mgm> show Connected to Management Server at: hostB:1186 Cluster Configuration

--------------------- [ndbd(NDB)] 2 node(s) id=3 (not connected, accepting connect from hostA) id=4 (not connected, accepting connect from hostB)

[ndb_mgmd(MGM)] 2 node(s) id=1 (not connected, accepting connect from hostA) id=2 (Version: 4.1.11)

[mysqld(API)] 2 node(s) id=5 (not connected, accepting connect from any host) id=6 (not connected, accepting connect from any host)

ndb_mgm> 1 status Node 1: not connected

ndb_mgm> 2 status Node 2: not connected

Regards, Nicolas Olivier Alphalink

Mikael Ronström wrote:

Hi, Your configurations file must be exactly the same on both management servers. All nodes need to be configured in all of them and if you ever change anyting in the configuration file you must ensure yourself that all active management servers always used the same configuration file.

Also with only 2 servers you can never get a fully HA system due to the network partitioning problem. See the docs on the why's.

Rgrds Mikael

2005-06-17 kl. 12.01 skrev Nicolas Olivier:

Hi,

I'm trying to setup a 3 nodes / host cluster. Meaning of this setup is for failover. So, in order to get that (in my mind), each host should run: - MGM node - Storage Node - SQL Node

NoOfReplicas is set to 2 for failover.

Using hostA and hostB, i've got the following config files:

On hostA:

/etc/mysql/my.cnf:

(...)

[mysqld] ndbcluster (...)

[mysql_cluster] ndb-connectstring = hostA,hostB

/var/lib/mysql-cluster/config.ini:

[ndbd default] NoOfReplicas= 2 MaxNoOfConcurrentOperations= 10000 DataMemory= 80M IndexMemory= 24M TimeBetweenWatchDogCheck= 30000 DataDir= /var/lib/mysql-cluster MaxNoOfOrderedIndexes= 512

[ndb_mgmd default] DataDir= /var/lib/mysql-cluster

[ndb_mgmd] Id=1 HostName= hostA

[ndbd] Id= 3 HostName= hostA

[ndbd] Id= 4 HostName= hostB

[mysqld] Id= 5

[mysqld] Id= 6

On hostB:

/etc/mysql/my.cnf:

(...)

[mysqld] ndbcluster (...)

[mysql_cluster] ndb-connectstring = hostB,hostA

/var/lib/mysql-cluster/config.ini:

[ndbd default] NoOfReplicas= 2 MaxNoOfConcurrentOperations= 10000 DataMemory= 80M IndexMemory= 24M TimeBetweenWatchDogCheck= 30000 DataDir= /var/lib/mysql-cluster MaxNoOfOrderedIndexes= 512

[ndb_mgmd default] DataDir= /var/lib/mysql-cluster

[ndb_mgmd] Id=2 HostName= hostB

[ndbd] Id= 3 HostName= hostA

[ndbd] Id= 4 HostName= hostB

[mysqld] Id= 5

[mysqld] Id= 6

The problem is that when I run try to start the two ndb_mgmd (hostA then hostB), the second fails with: Could not alloc node id at hostA port 1186: No free node id found for ndb_mgmd(MGM).

But as said in the doc, id are set explicitely for each node.

If anyone has an advice.

Mikael Ronstrom, Senior Software Architect MySQL AB, www.mysql.com

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