Single MID Server Instances or Multiple MID Server Instances.

[daray]

Greetings!

I am in the process of deploying ServiceNow in our company.   I wish to import ADDM data into our CMDB and wish to integrate AD authentication.   It does appear that using MID servers are the secure and correct way to do this.   Ideally, I plan on building these MID Servers on VMware guests,   and clustering the MID servers.   What I don't know is:   Do I want one MID server per guest with multiple capabilities configured or multiple MID server instances with one capability per instance.

[Mark Stanger]

Okay, you kept saying authentication so I was confused.   I still don't think there's any need for multiple MID servers unless you see an issue with connectivity, load, or redundancy.   I'd say a 2 total MID servers, each running for 2 capabilities, would be just fine as long as you space the scheduled imports out enough so that they don't get hit with requests for both at the same time.

[poyntzj]

OK, bearing in mind as Mark says, AD authentication is not performed by a MID server, it is just LDAP Imports.

I think you are going a little overkill to be honest.

I have 3 x   MID servers as they are regional.   We have this done due to the locations, some restrictions on the discovery. process.

However, we did establish that for our discovery the links from EMEA to APAC and Americas would cope with our loading

Our MID Server's OS is windows on a VM (dual proc, 4GB RAM) and we are running 3 instances of the MID server on each VM - DEV, Test and Production

I rarely see a problem with our servers and so far the are not struggling.   your loadings may change this.

Without trying I am not even sure what Servicenow will do

1. VM1 has MID server A1 for "ADDM" and A2 for "other"
2. VM2 has MID server B1 for "ADDM" and B2 for "other"

1. A load balance cluster of A1 + B2
2. A load balance cluster of A2 + B1
3. a failover cluster of A1 + B1
4. a failover cluster of A2 + B2

The load balance is putting the load between the 2 VM's

If VM1 fails, then everything should potentially run on VM2 and visa versa

Would need testing to make sure it does do this

[poyntzj]

Oh, if it helps in your calculations,

our LDAP is split into importing groups every 4 hrs and the main users every 6 hrs

The regions are split so the do not all run at the same time and in total it is around 25k users and 400 imported groups

We do have some other very specific ldap imports, but they are minimal and run at various times.