Anyone using IIS/NLB in a multi-machine deployment?

[ThomasColson]

Starting to seriously contemplate better failover. Any using https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2012-R2-and-2012/hh... in this scenario?

[ThomasColson]

Can you expand on that? Are you saying that if using Multiple-machine deployment with ArcGIS Web Adaptor—ArcGIS Server (Windows) Installation Guide | Arc... , I can unregister a machine at a time, do my maintenance, but I'm not clear at what point do I (re-create? re-register) the site? It's the last machine step that's confusing. My goal is to have more uptime during maintenance, with performance as a side benefit but not requirements, I'm (hate to say happy but....) with my server performance, the bottleneck is SDE which I don't have the resources to solve (no desire to run a cluster or a mirrored DB farm). Another consideration is out of hundreds of services, only 2 are hosted, with perhaps a 3rd in the distant next 5 years. Everything else is a registered SDE DB. Another philosophical question is there any advantage, in this configuration, to adding a second web adapter and load balancing requests to the WA (which in turn is load balancing requests to the servers), or stick with a single WA and a simple multi-machine site? 

[ThomasColson]

Jonathan Quinn‌ are there any updates on getting that documentation updated with what deployment scenarios can't be federated? 

[JonathanQuinn]

It hasn't made it in yet, but we're working on it. We plan to add a bullet under the Disadvantages section within the active/active and active/passive help, add it as a note to the Configure a hosting server for your portal section, and the add it to the advantages of multi machine sites here and here.

[ThomasColson]

Is there another source of this information? We're needing to make some configuration decisions rather soon. 

[JonathanQuinn]

Not that I'm aware of. What other questions do you have when considering active/active or active/passive using the silo architecture vs multi-machine sites?

[ThomasColson]

Of all the possible deployment scenarios, which can't be federated with Ptl?

[JonathanQuinn]

The only deployment scenarios that can't be federated are the ones that use silo-ed, mirrored environments, (i.e. active/active and active/passive)

[ThomasColson]

so Multiple-machine deployment with ArcGIS Web Adaptor—ArcGIS Server (Windows) Installation Guide | Arc...  is good for federation then?

[JonathanQuinn]

Yes, since the federation information is kept within the configuration store, the active/active or active/passive single machine deployment model won't work as each site has their own config-store. Making sure that each site creates the same service which is tied to the same item in Portal, (where the authentication is occurring), is impossible.

The multi-machine site approach, (either using the web adaptor or not), is the only way to set up a highly available/horizontally scaled ArcGIS Server site that is federated with Portal, since all machines are connecting to the same configuration store.

[ThomasColson]

Which is where I'm headed. I must admit, simply adding two more machines to a site with shared config has increased uptime substantially.