Question
· Aug 4, 2021

Azure Mirroring - VIP

Has anyone firstly got VIP working for mirroring in Azure?  We are pretty sure that this won't work but I wanted to verify it.

Has anyone used the Azure Load balancer to act as a Virtual IP and if so was a application gateway required.

Interested to know your experiences in getting this working.

Product version: IRIS 2020.4
Discussion (9)1
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Hello Jennifer,

While ISC docs are down currently, here's a web archive link to the section that discusses VIPs in the cloud:

https://web.archive.org/web/20201026104034/https://docs.intersystems.com/irislatest/csp/docbook/Doc.View.cls?KEY=GHA_mirror_set

"Typically, a VIP cannot be used in cloud environments. For a review of the options for configuring application redirection following failover in a cloud environment by an InterSystems Principal Technology Architect, please see Database Mirroring without a Virtual IP Address on InterSystems Developer Community."

Here are links to that and another potentially useful article on the community.

https://community.intersystems.com/post/database-mirroring-without-virtual-ip-address

https://community.intersystems.com/post/intersystems-example-reference-architecture-microsoft-azure-resource-manager-arm

Hello Oliver,

I read a few post of yours and came to understand that you were attempting to get mirroring setup, on Azure. We also have a similar requirement where we are trying to setup mirroring . The available options were:

1. Use IKO (containerised setup)

2. Use VMs to setup mirroring

We are able to not setup IKO on Azure and the fall back of setting up mirroring on Azure may also not be possible as per the above comments. Is that still the case? Did you overcome this situation somehow?

Hi Jennifer,

first things yes mirroring is supported in AWS and Azure. What is not working is the automatic VIP failover managed by IRIS. This is due to limitations imposed by the cloud providers, as you cannot dynamically add an IP address.

For this usually a loadbalancer is utelized, that queries a specific csp page on the mirror servers to decide which mirror is active and redirect the "VIP" accordingly.

Also depending on what access (application,xDBC) you need, you can deploy a load balanced array of web servers. These can host the webgateway, which in turn can be configured to be mirror aware and does no tneed a VIP to automatically failover.

Best Regards

Timo