Connection Tracking Problems

December 22nd, 2015

A couple of years back I discovered that when a VoIP server would sporadically lose it’s registration to the upstream VoIP provider, and then in spite of re-sending those registration requests would seem completely unable to register. Sometimes when rebooting the device it would then manage to reregister but not always. Read the rest of this entry »

The Abomination that is Android

August 26th, 2015

Over the years I’ve used Ericson and Nokia phones mostly. When it became time to start moving into the “smart phone” arena I got a Nokia N9. Then a Samsung Galaxy Note 2, and now the Note 4. Migration (between Android phones) is harder than it should be. Much harder. Read the rest of this entry »

GlusterFS – migration woes

May 17th, 2015

So I’ve got a GlusterFS cluster that is a simple 1×2 distribute-replicate with two bricks (one on each server). So I need to migrate this from one data centre to another with little or no downtime (which means move one server, perform heal, and then go and shut the other and move it too).

Unfortunately I got stuck in the middle with the moved server not wanting to talk with it’s peer again. As it turns out changing the IPs is … hard. Fortunately I used Private (RFC1819) IP addresses in the original setup on a dedicated cable between the two servers.
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Denial of Service

April 2nd, 2015

Denial of Service attacks is a very vague term for a group of attacks that causes a service to be denied to legitimate users. Obviously when you host your website publicly you want it to be available – so having it taken down by some hacker is highly annoying. And I’m not referring to only websites, there are many other types of applications and services out there that can be “taken down”, or to which “service can be denied”.
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