Little Nix/BSD routers & WAN link emulation..

[PiqueABoo]

[..that you may or may not want to run in VMWare]

 

Having skimmed the wikipedia entry on network emulation someone pointed me to in a thread that's wandered off somewhere, they're either expensive which I don't want or care about (very rough approximations of slow links is fine) or suprisingly big e.g. want 1/2 GB RAM.

 

Apparently Linux kernel 2.6 has NetEm. So has anyone seen any little router/firewall distros that might have the right bits in it, but not the kitchen sink?

[PiqueABoo]

Soo.. I messed around a bit more with the Dummynet vm.. turned off sendmail, syslogd, usbd, cut down the ttys and reduced the vmware memory to 64MB... and it still does the job.

 

Then looked at vmware's NAT, discovered it's just a bit lacking so tried turning NAT on in a clone of the above vm, but naturally the required option wasn't compiled in the kernel (Global conspiracy: "That NT bloke will probably wander by and want that one day, so let's turn it off!")

 

Then went hunting for little Linux firewalls, found several but so far none will cope with internal router/subnets. Couldn't face wading through other folk's interesting custom scripts to figure out how/where I could safely put what I wanted, so went back to FreeBSD for consistency and installed two v7.0's, one to rebuild the kernel, the other just to be much smaller, copied kernel from A to B and that works - only downside is the virtual disk after a minimal FBSD 7.0 install is about 280MB.

[PiqueABoo]

Further adventures: Went back to the FBSD kernel building box and played with tinyBSD which rebuilds and rounds up the files for a little version and throws it in a disk image. That has a couple of loose ends, but you can tweak those away before throwing the image at a 'real' disk.Turns out the smallest disk you can make in VMware is 102MB, but the one I made doesn't grow beyond 27MB.

 

The two DummyNet routers (adding 'slowness') are happy so far with 32MB RAM, ditto for the NAT router I had to put upstream of those as a workaround for vmware's NAT being a bit dumb.

 

Just need to remember what I was doing this for in the first place now..