Monday, 29 June 2009

Learning everyday....

Been a while since posting here, learnt a few things during that time.

Booting into runlevel 3 by default can have some odd side effects when you've spent time building scripts in runlevel 5.

Namely, I discovered my backup script wouldn't work for some reason when I tried to fire it off from the command line. I had taken the command generated by GRsync GUI and put it in a #! script so I could run from where ever and not have to remember the command and the flags I was using.

After a bit of poking I determind the backup disk had died. Or so I thought.
I log in locally, startx up x and no disk available. It used to live under /media/backup but it just wasn't there.

Discovered lshw to find out about hardware in the system, that reported the disk was present. So hopefully it was a config thing rather than hardware failure as first feared.

My GRsync (that I had originally used to launch the backup process) wouldn't run either.

Experiment time... logout of X, su and change the run level back to 5 (init 5). Login as regular user and presto, backup works again.

Seems running startx to get to desktop rather than switching run level means some script or other (presumably in /etc/rc5.d) that mounts the backup disk isn't being fired.

Another useful little program I've discovered during investigations is conky. A system monitoring tool. When first launched it is really dull looking black/white, but with the addition of a .conkyrc file to my home area it can be customised very heavily. A quick bit of googling brings up loads of screenshots with sample .conkyrc files to play with.

Been experiencing some strange behaviour with Banshee recently too... when downloading a podcast from the BBC, one one box (FC11 64bit) any - or _ characters in the filename get stripped.
On my home machine (FC10 32bit) the - and _ are left alone and remain in the filename.

On the face of it that wouldn't be an issue so long as each Banshee can find the files right? Problem is I want to setup a process to keep the two postcast directories in sync, so if one or other machine doesn't get turned on the other would make the download. Redundancy if you like to make sure I get the podcast!

Not worked that one out yet :/

Wednesday, 3 June 2009

Dynamic DNS (contd.)

Turns out I was looking in the wrong place in my router config. I was expecting it to live under the firewall options and open a port there, but instead it is actually under 'Virtual servers'.

Ahh well, either way it works now and I can get CLI access from anywhere to my home machine via SSH :)

Monday, 1 June 2009

Playing with DynDNS

My router is an older one. But it was a good one when I chose it, still does the job even if it can't support latest WiFi encryption tech (so have to rely on WEP!).

What it dows support however is out of the box dynamic DNS. So having a play with it last night and getting some odd results.

If I give my browser the magic URL it goes out, get redirected to my router, which passes the request to a http instance on my LAN (I assume the first one it finds) and passes results back to the browser. So as a proof of concept, I'm happy.

Now the server it is finding is my dev server, which I have not yet put any effort into nailing down http.conf so it displays the default 'welcome to fedora/apache instance' page. Not good.

Simple thinks I, I only want Dynamic DNS for use with SSH so I'll turn on firewall blocking of all ports but the ssh port.

Added to IPTables config on the macine and (re)started IPTables but still the machine seems to be serving out html from httpd :(

Looked at whether I could block incoming requests by port in the router firewall, but not found the options I need yet. I'm sure they should be there somewhere.

Maybe playing with these things at 1 in the morning is not such a good idea :/
Needless to say I switched off DynDNS in my router and PC is now off :P