QueueMetrics > Running QueueMetrics

Load balancing queuemetrics?

(1/3) > >>

barryf:
Hi,

Is it possible to load balance QM, using two tomcat servers?

I have a pair of servers set up with database replication and QM/Tomcat installed on both. I set both servers in DNS for round-robin load balancing, but it appears that the session breaks down when a user hits the other server.

Any way around this?

Thanks.

-Barry

QueueMetrics:
The session is theoretically serializable and so it should be movable in a well configured cluster... but that's not what I would do.

I would create a master-slave MySQL scenario (or use only one MySQL) and have two separate QMs with the same config that access the same database.


We have a few clients that actually set up a master-master MySQL replica as in here: http://queuemetrics.com/manuals/QM_AdvancedConfig-chunked/ar01s10.html (note that the article is still "in progress").

barryf:
Hi,

I have MySQL Master-Master replication in place. The problem appears to be that when a client browser switches from one QM instance to the other, the session information is not there and so QM throws an authentication error. The client would present the JSESSIONID cookie, but this would not be recognized by the other QM instance.

QM does not store its session state in mysql.

-Barry

QueueMetrics:
No it keeps it in RAM ,and may be quite large. So we suggest using sticky sessions if you ever need it to do load-balancing.

barryf:

--- Quote from: QueueMetrics on August 26, 2010, 11:25:39 ---No it keeps it in RAM ,and may be quite large. So we suggest using sticky sessions if you ever need it to do load-balancing.


--- End quote ---

FEATURE REQUEST: have an option to store session information in MySQL (or memcached) ;-)

This would make load balancing much easier, and allow you to expire out of memory sessions which have not been used for a while, but still retrieve them if needed.

-Barry

Navigation

[0] Message Index

[#] Next page