In this article, we’ll build a highly available IRIS configuration using Kubernetes Deployments with distributed persistent storage instead of the “traditional” IRIS mirror pair. This deployment would be able to tolerate infrastructure-related failures, such as node, storage and Availability Zone failures. The described approach greatly reduces the complexity of the deployment at the expense of slightly extended RTO.

++ Update: August 1, 2018

The use of the InterSystems Virtual IP (VIP) address built-in to Caché database mirroring has certain limitations. In particular, it can only be used when mirror members reside the same network subnet. When multiple data centers are used, network subnets are not often “stretched” beyond the physical data center due to added network complexity (more detailed discussion here). For similar reasons, Virtual IP is often not usable when the database is hosted in the cloud.

Network traffic management appliances such as load balancers (physical or virtual) can be used to achieve the same level of transparency, presenting a single address to the client applications or devices. The network traffic manager automatically redirects clients to the current mirror primary’s real IP address. The automation is intended to meet the needs of both HA failover and DR promotion following a disaster.

I have been working on redesigning a Health Connect production which runs on a mirrored instance of Healthshare 2019. We were told to take advantage of containers. We got to work on IRIS 2020.1 and split the database part from the Interoperability part. We had the IRIS mirror running on EC2 instances and used containers to run IRIS interoperability application. Eventually we decided to run the data tier in containers as well.

++Update: August 2, 2018

This article provides a reference architecture as a sample for providing robust performing and highly available applications based on InterSystems Technologies that are applicable to Caché, Ensemble, HealthShare, TrakCare, and associated embedded technologies such as DeepSee, iKnow, Zen and Zen Mojo.

Azure has two different deployment models for creating and working with resources: Azure Classic and Azure Resource Manager. The information detailed in this article is based on the Azure Resource Manager model (ARM).

InterSystems IRIS Deployment Guide for AWS using CloudFormation template

If you're running IRIS in a mirrored configuration for HA in Azure, the question of providing a Mirror VIP (Virtual IP) becomes relevant. Virtual IP offers a way for downstream systems to interact with IRIS using one IP address. Even when a failover happens, downstream systems can reconnect to the same IP address and continue working.

The main issue, when deploying to Azure, is that an IRIS VIP has a requirement of IRIS being essentially a network admin, per the docs.

To get HA, IRIS mirror members must be deployed to different availability zones in one subnet (which is possible in Azure as subnets can span several zones). One of the solutions might be load balancers, but they, of course, cost extra, and you need to administrate them.

In this article, I would like to provide a way to configure a Mirror VIP without the using Load Balancers suggested in most other Azure reference architectures.

With the world (as well as our own technology) moving to the cloud at such a fast pace it is easy (at least for myself) to get caught up in the little details. One thing I, and some clients of ours, had run into a couple of times was the necessity to specify the version of the images one plans to use with the IKO.

If you're running IRIS in a mirrored configuration for HA in GCP, the question of providing a Mirror VIP (Virtual IP) becomes relevant. Virtual IP offers a way for downstream systems to interact with IRIS using one IP address. Even when a failover happens, downstream systems can reconnect to the same IP address and continue working.

The main issue, when deploying to GCP, is that an IRIS VIP has a requirement of IRIS being essentially a network admin, per the docs.

To get HA, IRIS mirror members must be deployed to different availability zones in one subnet (which is possible in GCP as subnets always span the entire region). One of the solutions might be load balancers, but they, of course, cost extra, and you need to administrate them.

In this article, I would like to provide a way to configure a Mirror VIP without using Load Balancers suggested in most other GCP reference architectures.

NB. Please be advised that PKI is not intended to produce certificates for secure production systems. You should make alternate arrangements to create certificates for your productions.
NB. PKI is deprecated as of IRIS 2024.1: documentation and announcement.

InterSystems FAQ rubric

If you do not specify the option to remove the mirror attribute of the mirror database when deleting the mirror configuration, the database cannot be restored to a normal state and will be mounted read-only the next time it is mounted. To restore the database to a read-write state, you must remove the mirror attribute using the system routine ^MIRROR.

The procedure is as follows (execute in the %SYS namespace):

Here are a few tips that might be useful to people who are running applications in an environment that's configured to use InterSystems mirroring.

I had a question about using ZSTART, ZSTOP, and ZMIRROR.

• If we use them and it is not correct, does it mess up with any of the existing functionality?
• So, if I create a ZSTART with a simple command of starting the %JDBC Server will that mess up anything existing in the Startup sequence?
• Is ZSTART, ZSTOP, and ZMIRROR just an extension of the existing functionality, or does it alter how the built in functionality runs?
• Should we tread lightly in the use of them?