Two more pixes arrived, bought second hand on Ebay, delivered by Parcelforce. Some people have the plural as "pixen", but that's just too twee. These are pix 515e boxes, and I'm in the middle of copying the configuration that I've been setting up on the pix 525, onto the new pix. And it seems to be transferring without any difficulties.
The pixes came as a pair, costing £80, which is still a very good buy. The reason they're a pair, is failover. The idea is that if one of them stops working, for whatever reason, the other one picks up the load without a pause. On the other hand, I've been running the pixes I already have, non-stop for several years without a single failure. They are just that well made.
Unlike the Sonicwall. You don't want to hear about the sonicwall.
The pix I'm working on now, has six ports. One for inside, one for outside and one for the dmz. And three that I don't think I'll use (although one might be useful for the failover communication). It has 64 mb of memory, which might not sound like much, but the one I'm using to pass through 100 mbits is currently using only 16 mb of its 32 mb total, so I'm thinking that 64 mb will be plenty.
But I notice that the failover pix only has two network ports, which means I don't see how it can be used as a failover - there's no dmz. But I'm wondering if I can take one of the four-port cards out of the pix525 and install it in the pix515. It's worth a try!
The pix 525 will continue to the useful, even though it automatically reboots every 24 hours. I'll use it as a test bed for trying out configurations - you don't want to do experiments on a system that working full blast, because if you mess up the configuration of a firewall, you can suddenly cut off all communications.