Busy busy busy (by alaric)

Well, the furnace plans are having to wait until I get some time to go outside and blast the refactory material samples with the blowtorch to see how they perform...

I've been really very busy. When we decided to have a baby, my plan was to take on loads of contracts during the early stages when she wouldn't need all the looking after so I could save up spare cash and then take the work a bit easier when she needs me most, and when we have a new child to be fascinated by!

However, as luck would have it, several independent jobs have all ended up overlapping their deadlines to the same week a while back, at the same time as everyone deciding to have major important parties every evening and weekend (which, to us living out here in Zone 6, means a two-hour journey in and out, often getting home REALLY late when there's no option of sleeping in the next day)... so I've just kept my nose to the grindstone.

And Sarah's not been very well; morning sickness kicked in pretty early for her, along with growing back pains due to the increasing weight, and she's been more prone to colds lately, presumably due to her bodily resources being tied up elsewhere!

But now the deadlines are starting to pass, leaving me with just the glut of non-important work that I couldn't do because I was busy with deadlines, so now need to sort out. Paperwork, that sort of thing.

Today, I'm getting replacament hardware for love, my main hosting server, ready. It's a nice fast machine, and the current machine is going to become an NFS and database server for this one - without an external IP address, it's going to connect to it with a loopback cable, and basically just be an external disk pack with brains. The actual upgrade will occur sometime next week, but I need it ready today because today is my one chance to get a lift into London on a car, whereupon I will leave it over with a friend until a day the hosting place is open.

Furnace – MARK 3 (by alaric)

Ok! Right!

Furnace Mark 1 was made in a coffee can, and was a bit too small. The crucible it was designed for was too small to pour some of the things we decided we wanted.

So we made the Mark 2, which was bigger. And then it was nearly ruined when a crucible (thin steel cup, since I can't find any iron pipes anywhere, and couldn't weld until recently) leaked molten Al everywhere, so we moved up to Salamander crucibles. And then we had to make crucible tongs, since we couldn't fit them with lifting lugs. And the Mark 2 turned out to not have enough clearance to fit the tongs around a crucible inside, as well as the inside having gotten rather crumbly and fallen to bits a lot. We tried to chop it down the side so one half of it (except for the base) could be removed to get the tongs in, but it just turned to power.

So on to Mark 3. Read more »

Sarah’s Pregnant! (by alaric)

Due July/August 2005. Watch this space!

Apple Macs (by alaric)

I've always been somewhat attracted to Mac OS X - the combination of a UNIX system and a mainstream consumer OS with GUIs and the other nice stuff you get form a modern commercial system seems too good to be true.

However, a project I'm working on looked like it'd be easiest if I had the same OS to compile it on as the other developer (thanks to the build system, which turned out to be a bit less platform independent than one mimght like), so I picked up a second-hand G4 with OS X.

It seems nice; I've only crashed it twice (once with a nice clean kernel panic when an NFS mount went bad, the other time it just mysteriously froze for no apparent reason), which isn't that bad really. iTunes is really nicely designed, and it's a totally new experience to me to have a mail client that actually shares an address book with my Handspring Visor!

I wish I could use a more normal keyboard, however, I don't like where the tilde is, and that " and @ are the wrong way round, and that # is hard to get. I tried plugging in a USB keyboard with a layout I liked, but much to my horror, it still thought it was a Mac keyboard and just produced the character a Mac would have when pressing the key in that position, regardless of the decal on the key... I'd always imagined that USB keyboards would be sensible and send Unicode characters, plus special codes for function keys, rather than still doing all that keymap scancode stuff that traditional PC keyboards do. Oh well.

More on little firewalls (by alaric)

Ok, I've picked up two Soekris net4801s. Lovely little boxes!

Installing OpenBSD on them via PXE was trivial. One interesting point was that I was running them from a 6v power supply, since the thing requires from 6 to about 28 volts. Presuming this to mean there's a linear regulator within generating a 5v line, I ran it from 6v to reduce the losses in the linear reg.

Anyway, all was well, until the box started to refuse to reboot. I was puzzled for a while, then I increased the voltage on my (cheap, unregulated) power supply unit. At first I thought my cheap little power brick was probably undervolting, but when all power to the area went down (including the streetlights on the A127!), it occured to me that perhaps the mains power might have been a little under 240v anyway 🙂

I got two of them, one for the original transparent firewalling application, and another to play with that I've decided to use to replace my current home LAN router - a 486 desktop machine running NetBSD. I'm using Ethernet bridging to make it appear like a three-port Ethernet switch linking the DSL router, my DMZ network, and my internal network; the internal machines use a private IP range, while the DMZ network machines have both private IP and public IP addresses; the Soekris box acts as a packet-filtering transparent firewall between the three LANs, while also being a NAT router between the private IP range and a public IP address.

This all works fine, except that if a DMZ machine tries to talk to the internal IP address of the router (which runs a DNS server), the response comes back from the external IP of the router, and with a different source port, so isn't recognised by the DMZ machine as being a valid reply. I've worked around it by getting the DMZ machines to use the router's external IP as their DNS server, and telling the router to allow access to the DNS server via the external IP only from the DMZ, and moving more interface-dependent services like DHCP and broadcast NTP off of the router to a DMZ machine.