Q4 release - Is it ok to have multiple application servers installed on multiple physical servers, pointing to the same iMIS dat

We just installed the Q4 "application server" in a test environment.

If we want to host our public RISE site from a different server, do we need to install the "application server" again on that physical server?

IOW, is it possible, required, or recommended to have multiple "application servers" installed on multiple physical servers. They'd all point to the same iMIS database, of course.

Mike at APWA

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Hi Mike, If you have the

Hi Mike,

If you have the hardware capacity, I would definitely recommend splitting out your application servers to reduce the risk of outages and to spread the load across multiple servers. Some of our clients have an "internal" app server for staff to access the iMIS Desktop and Staff website, and a separate physical server for their public/member website. We also have clients that have implemented a Network Load Balanced (NLB) environment to share the load across multiple servers.

Having said that, there are some publishing concurrency issues in some versions of iMIS 20.2 when you have multiple publishing servers in the same server farm. You may encounter database deadlocks if you have multiple publishing servers. Thankfully, this should now be rectified in the latest interim releases (I believe this has been rectified in 20.2.49 and above).

To install a secondary server, you would install iMIS the same way you did on the primary server. Older versions of iMIS 20 and 15 included a "WCM" role in the installation, but this has been eliminated, so the approach to installing iMIS on multiple servers is the same as the primary app server (full iMIS installation).

Hope this helps.

James @ Bursting Silver


Your answer went way above and beyond run-of-the-mill helpfulness, thanks!

Mike Olin
American Public Works Association

NiUG presentation

I gave a presentation on this very question at the latest NiUG conference. If you're a member, you can get access to the video through the NiUG website. The panel was "Knowing your iMIS options," with Doug Morris as the main presenter. My part was about taking iMIS to the next level.

The short version: There are definitely options for scaling iMIS up and out. Creating a second server brings performance gains but administrative burdens -- it might or might not be the right move. Many clients configure more than one "web application" on the same IIS server, served from the same folder on disk. This gives you the performance and separation advantages of separate IIS websites, but with only one Publishing service, and only one copy of iMIS software to maintain.

Instead of just segmenting users (forcing staff to one site and the public to another), iMIS can also be configured in a true load-balanced arrangement. Each web visitor will be served by all web servers in the pool according to their available load. This requires some additional setup up front, but it allows the website to keep running even if one server becomes unavailable.

We applied some of our best-practices techniques when we set up your original server. This would have given you some performance benefits on your old install. Since you have configured the new server on your own, you might have taken a step back in performance. Making use of current best-practice tuneups should help noticeably without the headaches of an additional server.
Bruce Wilson
Senior Director, Technology Solutions


Thanks, Bruce. It was actually Shah who did all of the configuring, but I've pointed him to your comments.

Mike Olin
American Public Works Association

Exactly what I've been looking for

Hello Bruce,

I'm completely unable to find this presentation on the NiUG website. Could you share a link to same, please?