High Availability (also known as HA) is the capability of a system to remain online regardless the adversary events that might happen. Then, we will state that availability is the characteristic that concerns a service to be reachable when it is needed. And as you should guess, availability can be measured using percentages (from 0% to 100%); of course, we all know the more close to the 100%, the more expensive it is to deploy a system like that. In the folklore when you say a service has 3 nines of availability, you mean 99.9%., 

As a security consultant and CISSP certified, I have not found any hard definition that states how many 9's you should have in order to claim you have high availability. In my experience, people start calling high availability when you talk about 3 nines or better. But this is only a feeling.

When someone says in the cloud, it is a very gray term that means other's computer. When we speak about servers, we think about VPS'es in the cloud. A name such as Digital Ocean or Vultr jumps right away to my mind. If you are looking forward to having a non-expensive, reliable system in high availability with some load balancing, this article will help you to understand how this works.

Usually running the nice command with the correct priority could be enough to put a process in a using cap. But, nice doesn't limit CPU use, it does only a prioritization of processes. This means the given process will run using all CPU's power if there is no other process (with higher niceness) requiring the CPU. This is not the best in some cases, I found the project Cpulimit which it does put a CPU use cap based on the percentage.

Cpulimit is a tool which limits the CPU usage of a process (expressed in percentage, not in CPU time). It is useful to control batch jobs when you don't want them to eat too many CPU cycles. The goal is to prevent a process from running for more than a specified time ratio. It does not change the nice value or other scheduling priority settings, but the real CPU usage. Also, it is able to adapt itself to the overall system load, dynamically and quickly. The control of the used CPU amount is done sending SIGSTOP and SIGCONT POSIX signals to processes. All the children processes and threads of the specified process will share the same percentage of CPU.

FusionPBX is a WEB frontend for FreeSWITCH. It allows to do many things almost out of the box (don't take it wrong, it stills need configuration but you save time). FusionPBX as an in-app architecture that allows it to add different functionalities. These in-app are usually in the Advanced menu.

As I have already coding Billing for FusionPBX and RSVP for FusionPBX. I will share some of the know-how to do this. In this article, I will explain the anatomy of a basic in-app. This will help developers to do their own applications.

Ether-Proxy 0.5.2 RPMs for Mageia Cauldron (6) are now available since today. This is an ethereum mining proxy with web-interface. Proxy feature list:

  • Rigs availability monitoring
  • Keep track of accepts, rejects, blocks stats
  • Easy detection of sick rigs
  • Daemon failover list

I have tried with Parity 1.3.x and as far as I see it is working. It is not perfect, some things need to be added, but as a proxy, it works.

As part of my commitment with Mageia, I will try to keep this package as updated as possible. 

RPM's are available for Mageia Cauldron (6), I will be working to backport to Mageia 5 as soon as possible. You can install it if you type urpmi ether-proxy

Enjoy!

Syncthing 0.14.8 RPMs for Mageia Cauldron (6) are now available since today. Syncthing is a complete synchronization, multi-platform solution to have same files in your devices. It is like a Peer-to-Peer.

Syncthing is an excellent option if you have at least one road warrior involved. Since there is no warranty of a public IP or even a static IP, Syncthing architecture allows clients to bypass NAT's and allow file exchange. The good thing of Syncthing is it is available not only on Linux and Windows but Android as well. You can have in sync important files in your mobile or tablet.

Syncthing 0.14.x is not compatible with 0.13.x. You must update all your devices. Backport for Mageia 5 is more difficult as it seems. I am not able to reproduce it in the build system. Mageia 5 has Golang 1.4 which it is not compatible with Syncthing 0.13.x. Someone has ported back golang 1.6 into Mageia 5, this means you can compile syncthing under Mageia 5 using the SRPM without issues. To do this, you must enable the backport/release repository.

As part of my commitment with Mageia, I will try to keep this package as updated as possible. The team from Syncthing are very responsive and they release new versions very often. At the time when writing this article, Mageia Cauldron 6 is in version freeze; this means we will need to wait for a little until the big system administrators let the new RPM in.

RPM's are available for Mageia Cauldron (6), I will be working to backport to Mageia 5 as soon as possible. You can install it if you type urpmi syncthing.