Regular Expressions - RegEx

Regular expressions can be a bit like marmite, some people love them and some hate them, and if you are like me, they just leave lots of room for confusion.

Fortunately there is a tool that will hopefully dispel some of the confusion.

https://regex101.com/

 

(Read more...)

Autoscaling

One of the single best features of using cloud servers, is the ability to add servers to a cluster on demand.

Here is a useful article about autoscaling and why you should consider in in your application design.

https://blog.codeship.com/autoscaling-purpose-strategies/

(Read more...)

AWS ELB upgrade - Layer 7 Load Balancing

AWS have announced Application (level 7 on the osi model) Load Balancing.
I've been using HA Proxy to achieve this for a while now.
Load balancer diagram
What does this mean to us?
You can now load balance and direct traffic to a 'target group' of servers. This means you can use on ELB for a website whilst using multiple server groups for each microservice. For instance anything with /api in the url can get directed at a different group to those with /backend in the url. In current setups we are using subdomains to do this, api.webdomain.com and backend.webdomain.com.

Having Application Load Balancers will allow us to simplify and reduce the number of ELBs needed, thus saving money.

This and more features can be found on amazon's blog. https://aws.amazon.com/blogs/aws/new-aws-application-load-balancer/

 

(Read more...)

Happy birthday WWW

25 years ago, 1991, the WorldWideWeb was created.

The first website is still there. http://info.cern.ch/hypertext/WWW/TheProject.html

Back in the days when a NeXT was the best machine in the world. Thanks Steve.

 

(Read more...)

AWS biggest instance

Wow, today I noticed that AWS now provides a truly massive instance. By request at the moment.

vCPU ECU Memory (GiB) Instance Storage (GB) Linux/UNIX Usage
x1.32xlarge 128 349 1952 2 x 1920 SSD $16.006 per Hour

Above is the EU-WEST-1 (Ireland) pricing for an on demand instance. That equates to $384 per day.

I'm not sure we've seen a workload that could justify this monster. When configuring a cluster we would usually use smaller and many instances to match the load more closely.
In a monolithic environment this could be used as a single SAP HANA node or similar?

Of course we will update you when we find one in production.

(Read more...)