topic Re: Load Broker in Operating System - OpenVMS

Load Broker

Mahmoud_1 — Sat, 08 May 2004 06:46:43 GMT

Hi to all,
I have tow ES40 cluster systems running OpenVMS 7.3-2. I enabled the LoadBroker service and the Metric service to make load balance but I faced that the connections using the Cluster Alias always directed to the first system that I configured the TCPIP on. I defined alias name for the tow systems and the problem stil there, So how can I do this task.
The steps I did:
1- Configur the TCPIP for both nodes with same cluster alias.
2- Enable the Metric, Lbroker service's
3- Rename the TCPIP$LD_Broker_CONF.template to TCPIP$LD_BROKER.CONF
4- Customize the CONF file
Note:
My serviers address's
systema 172.29.10.70
systemb 172.29.10.71
Cluster Alias 172.29.10.72
Thanks for help.

Re: Load Broker

Kris Clippeleyr — Sat, 08 May 2004 08:42:52 GMT

Mahmoud,

Although I have no experience with the LoadBroker module in TCP/IP, I can tell you that when the first node boots in a cluster, and that node starts TCP/IP, the TCP/IP cluster alias is assigned to that node, and will stay there. The current implementation of the TCP/IP stack lacks the load balancing of e.g. DECnet OSI, or even LAT. To me, it's a major design flaw.

Greetz,

Kris

Re: Load Broker

Alex Daniels — Sun, 09 May 2004 04:31:32 GMT

The previous person who answered was talking about the old cluster impersonator, if he wants the load balancing facilities of LAT, he too should look at Load Broker.

You don't need a seperate 'Cluster Alias' IP address with Load Broker, Load Broker updates your DNS servers with the IP address of the least loaded box in your cluster.

In your conf file you should have put the IP address of your DNS server and on the DNS server, allowed updating from the IP addresses of the machine/s where you are running Load Broker.

Re: Load Broker

Mahmoud_1 — Sun, 09 May 2004 06:42:09 GMT

Hi Alex,
Thanks for answering me, but if you please will you tell me the exact syntax of the CONF file if I have:
DNS 172.16.0.5
Cluster_Member1 172.29.10.70
Cluster_member2 172.29.10.71
Cluster Alias 172.29.10.72

Best Regards.

Re: Load Broker

Alex Daniels — Sun, 09 May 2004 09:18:14 GMT

The concept is somewhat different so there is not a seperate IP address for the cluster alias.

If in DNS you have an entry for 'Clusteralias' it will point at either the address of cluster_member1 or cluster_member2 and be dynamically updated at intervals you specify in the conf.

So you can effectively remove the old clusteralias name from DNS as this will be recreated and then continually updated by Load Broker.

It also also a requirement that the DNS server is set to allow DNS updates from your boxes. Is it a BIND or windows DNS Server? If this has not been done, Load Broker will not be able to update the DNS and this won't work!!

Your conf should be something like this...

cluster "clusteralias.companyname.com"
{
dns-ttl 10;
dns-refresh 5;
masters {
172.16.0.5;
};
polling-interval 3;
max-members 1;
members {
172.29.10.70;
172.29.10.71;
};
failover 172.29.10.70;
};

Re: Load Broker

Mahmoud_1 — Mon, 10 May 2004 04:41:04 GMT

Hi,

I did all the steps but still I have the same problem the connection is to the first system I configured the alias on.

Do I have to define the Cluster Alias from The TCPIP$CONFIG or not ?

*** On the TCPIP prompt what I have to do **
Please advice.

Re: Load Broker

Mahmoud_1 — Mon, 10 May 2004 08:53:48 GMT

Hi to all,

In my case I am using telnet connection from PC's in students labs to the database server using IP addr. and I can's use name resolving so I have to issue telnet 172.29.10.72 ( the Cluster Alias IP Addr. ).

I put a text file contains my servers logg's

Please advice.

Thanks in advance