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A few weeks ago we launched op5live.com, an easy way to monitor your public web services and also to add an outside view / monitoring to your op5 Monitor - on premises. This is a SaaS service that we have built with Node.js, MongoDB using op5 Monitor in the back-end. All communication is done over the API to the backend core op5 systems.

The service is hosted at City Networks with two datacenters so geographically separated, load balanced and in full sync with each other. We also use Amazon to host our pollers in the US and in Frankfurt, Citynetworks pops in Stockholm/London. Stripe to support us on payments, Sendgrid for notifications and then it's all integrated to Salesforce for business analytics. So it's a truly distributed and hybrid set-up. 

Here are some examples on how we visualise this set-up in the internal op5 Monitor system we obviously use to monitor this service.

Note all the green icons representing a serie of services being monitored at every point. 

(click on image to see bigger picture)

 

The Dashboard is "mouse over" enabled so that it's easy to go directly to a potential warning.

And to make sure we are in operation - we use the Business service monitoring part of op5Monitor. This enables us to see that even if we have some technical warning or even faults - the service is in operation as we have redundancy for all major parts of the solution. 

And to finalise the monitoring - we use op5live:) to give us an outside view of the service, and then we use the integration between op5live and op5 monitor to enable so that op5live data gets presented as any other event in op5 Monitor's event flow.  

 

If you want to read more about how to use: 

 

Have great day! 

 

 

 

 

 

 

 

 

SSH is a secure way to connect to remote systems that run Linux or any other Unix operating system. SSH is fast, secure and runs everywhere. Additionally, it supports secure and convenient authentication methods and tunneling of TCP connections, beside of much more. But there are also some problems with SSH. SSH sessions loose connection when your IP address changes. Also, when working on a slow network connection, SSH sessions can get pretty unresponsive and slow, because every character that is typed at the client’s end is transferred to the remote host and acknowledged there in order to get displayed on your computer’s terminal window. On a slow mobile connection or even a crowded hotel WiFi an SSH connection can get nearly impossible to work with, because of the high lag.

Mosh stands for “Mobile Shell” and is an application that allows roaming, supports intermittent connectivity, and provides intelligent local echo and line editing of user keystrokes.

Mosh uses ssh for the initial authentication through TCP. After successful authentication, mosh switches to use the UDP protocol. Your terminal commands will be transferred over an encrypted UDP connection where the UDP communication port number identifies the connection (very simply spoken). That means, that there is no need for an established TCP connection in order to be able to type commands. This way, when you change your IP address or get disconnected and reconnected again, the terminal connection will just continue at where you were before.

SSH waits for the server's reply before showing you your own typing. That can make for a lousy user interface. Mosh is different: it gives an instant response to typing, deleting, and line editing. It does this adaptively and works even in full-screen programs like emacs and vim. On a bad connection, outstanding predictions are underlined so you won't be misled.

Mosh doesn’t need a server daemon, it runs as a simple binary and doesn’t even need root permissions. It’s available for nearly all platforms from the mosh web site https://mosh.mit.edu and from the packet repositories of major linux distributions. 

The mosh command can be used pretty much as a replacement for the ssh command. 

Instead of

ssh myserver

you will type:

mosh myserver

I am using mosh now for several weeks now and I really enjoy not having to reconnect to my systems every time I switch from LAN to Wifi, or when I jump into a train etc. Also, being able to still type commands fluently even though the connection is stalled or horribly slow is very nice.

Get mosh here: https://mosh.mit.edu, check the tech video: https://mosh.mit.edu/#techinfo and start mosh’ing right now!

Linux kernel update

A bug has been discovered in the Linux kernel, affecting most Linux-based systems. The impact on an APS system is primarily a risk of crashing the system, but theoretically it is possible to gain unauthorized access to the system.

The bug is related to how the kernel handles netfilter.  A remote attacker could use this flaw to send a specially crafted DCCP packet to crash the system or, potentially, escalate their privileges on the system. (CVE-2014-2523)

The kernel update also contains bug fixes for Adaptec RAID controllers and QEMU. An APS customer should not be affected by these problems, but customers running RHEL or CentOs might be affected. op5 recommends reading the Red Hat announcement for further information.

op5 recommends to regularly update the APS system to ensure that the system is as secure as possible. For information of how to update op5 software please read the manual section about administrative tasks. A new installation iso for APS is available at our downloads page.