The Question Recently, a customer asked us:

How would we manually move the relay role from a failing node to a slave in a Composite Tungsten Cluster passive site?

The Answer The Long and the Short of It

There are two ways to handle this procedure manually when the usual switch command fails to work as expected. One is short and reasonably automated, and the other is much more detailed and manual.

Of course, the usual procedure is to just issue the switch command in the passive cluster:

use west
set policy maintenance
switch
set policy automatic

The below article describes what to do when the switch command does not move the relay role to another node.

SHORT

Below is the list of cctrl commands that would be run for the basic, short version, which (aside from handling policy changes) is really only three …

We’re pleased to share our webinar “Multi-Region AWS Aurora vs Continuent Tungsten for MySQL & MariaDB”, recorded live on Thursday, April 18th, 2019.

Our colleague Matt Lang walks you through a comparison of building a global, multi-region MySQL / MariaDB / Percona cloud back-end using AWS Aurora versus Continuent Tungsten.

If you’d like to find out how multi-region AWS Aurora deployments can be improved – then this webinar is for you!

We hope you enjoy it!

Recorded:

Thursday, April 18th at 10am PST / 1pm EST / 4pm BST / 5pm CEST

Recording: follow this link to watch

Slides: …

In case you missed the Multimaster webinar recorded live on Thursday, March 28th, 2019:

Learn how NewVoiceMedia built a global, multi-region MySQL cloud back-end to support a high-volume cloud contact center. 

Agenda:

Find out how to deploy Multimaster MySQL / MariaDB / Percona with the following design criteria:

• Geographically distributed, low-latency data
• Fast local response times for read & write traffic
• Full ACID compliance – atomic operations, guaranteed consistency, isolation, and durability
• Local rapid-failover, automated high availability

Speaker:

Chris Parker

Director of Professional Services – EMEA/APAC, is based in the UK, and has over 20 …

For those of you who missed the webinar, “Geo-Scale MySQL in AWS,” recorded live on Thursday, March 14th, 2019:

Learn how to build a global, multi-region MySQL / MariaDB / Percona cloud back-end capable of serving hundreds of millions of online multiplayer game accounts.

Agenda:

Find out how Riot Games serves a globally distributed audience with low-latency, fast response times for read traffic, rapid-failover automated high availability, simple administration, system visibility, and stability.

Speaker:

Eric M. Stone

COO at Continuent, is a veteran of fast-paced, large-scale enterprise environments with 35 years of Information Technology experience. With a focus on HA/DR, from building data centers and trading floors to world-wide deployments, Eric has …

In Amazon space, any EC2 or Service instance can “disappear” at any time.  Depending on which service is affected, the service will be automatically restarted.  In EC2 you can choose whether an interrupted instance will be restarted, or left shutdown.

For an Aurora instance, an interrupted instance is always restarted. Makes sense.

The restart timing, and other consequences during the process, are noted in our post on Aurora Failovers.

Aurora Testing Limitations

As mentioned earlier, we love testing “uncontrolled” failovers.  That is, we want to be able to pull any plug on any service, and see that the environment as a whole continues to do its job.  We can’t do that with Aurora, because we can’t control the essentials:

• power button;
• reset switch;
…

Right now Aurora only allows a single master, with up to 15 read-only replicas.

Master/Replica Failover

We love testing failure scenarios, however our options for such tests with Aurora are limited (we might get back to that later).  Anyhow, we told the system, through the RDS Aurora dashboard, to do a failover. These were our observations:

Role Change Method

Both master and replica instances are actually restarted (the MySQL uptime resets to 0).

This is quite unusual these days, we can do a fully controlled role change in classic asynchronous replication without a restart (CHANGE MASTER TO …), and Galera doesn’t have read/write roles as such (all instances are technically writers) so it doesn’t need role changes at all.

Failover Timing

Failover between running instances takes about 30 seconds.  This is in line with information provided in the …

If you’re in Barcelona next week you may be interested in the MySQL Meetup being held there by the Barcelona MySQL Meetup group on Wednesday 7th July at 7pm. I’ll be doing a talk on MySQL Failover and Orchestration and there will be opportunity to talk about MySQL and related topics afterwards. More information can … Continue reading Barcelona MySQL Users Group Meetup on 5th July

The post Barcelona MySQL Users Group Meetup on 5th July first appeared on Simon J Mudd's Blog.

Please join Percona’s Jon Tobin, Director of Solution Engineering at Percona, and Rob Masson, Solutions Architect Manager at ScaleArc, on Thursday, January 26, 2017, at 9:00 am PST / 12:00 pm EST (UTC-8) for their webinar “Overcoming the Challenges of Databases in the Cloud.”

Enterprises enjoy the flexibility and simplified operations of using the cloud, but applying those advantages to database workloads has proven challenging. Resource contention, cross-region failover and elasticity at the data tier all introduce limitations. In addition, cloud providers support different services within their database offerings.

Jon and Rob’s webinar is a …

Join Percona’s Chief Evangelist Colin Charles on Wednesday, January 18, 2017, at 7:00 am (PST) / 10:00 am (EST) (UTC-8) as he presents “Lessons from Database Failures.”

MySQL failures at scale can teach a great deal. MySQL failures can lead to a discussion about such topics as high availability (HA), geographical redundancy and automatic failover. In this webinar, Colin will present case study material (how automatic failover caused Github to go offline, why Facebook uses assisted failover rather than fully automated failover, and other scenarios) to look at how the MySQL world is making things better. One way, for example, is using …

In this post, I’ll discuss how to moving VIPs during a failover using Orchestrator.

In our previous post, we showed you how Orchestrator works. In this post, I am going to give you a proof-of-concept on how Orchestrator can move VIPs in case of failover. For this post, I’m assuming the Orchestrator is already installed and able to manage the topology.

Hooks

Orchestrator is a topology manager. Nothing less nothing more. In the case of failover, it will reorganize the topology, promote a new master and connect the slaves to it. But it won’t do any DNS changes, and it won’t move VIPs (or anything else).

However, Orchestrator supports hooks. Hooks are external scripts …