Mixing pysnmp and stdin

Depending on the application, sometimes you want to have some socket operations going (such as loading a website) and have stdin being read. There are plenty of examples for this in python which usually boil down to making stdin behave like a socket and mixing it into the list of sockets select() cares about.

A while ago I asked an email list could I have pysnmp use a different socket map so I could add my own sockets in (UDP, TCP and a zmq to name a few) and the Ilya the author of pysnmp explained how pysnmp can use a foreign socket map.

Checking Cloudflare SSL

My website for a while has used CloudFlare as its front-end.  It’s a rather nice setup and means my real server gets less of a hammering, which is a good thing.  A few months ago they enabled a feature called Universal SSL which I have also added to my site.  Around the same time, my SSL check scripts started failing for the website, the certificate had expired apparently many many days ago. Something wasn’t right.

Juniper Firewalls and IPv6

A little firewall

I found an interesting side-effect of the Juniper firewalls when you introduce IPv6.  In hindsight it appears perfectly reasonable but if you are not aware of it in the first place you may have a much more permissive firewall than you thought.  My setup is such that my internet address changes every time I connect to an ISP. I have services “behind” the Juniper that I want to expose onto the Internet, in this case a mailserver.