“fsnet_create” a good plan?

Week 8 :-

I think I have found my footing. Here is a design diagram. I am considering creating a fsnet which is more or less equivalent to inet – and perhaps even borrows / wraps some code -  except that it provides functions to the libfs based netfs implementation program.

The inet function in question can be found at net/ipv4/af_inet.c

Glendix on Routers?

Glen-concept #1

Glendix for routers? I was poking around for what it would take to get there. I found this. I am basically looking to have a way to do routing using Glendix. You can already do that on any standard Linux using Quagga (see http://www.quagga.net/docs/quagga.html#SEC3 ). They use a traditional dynamic library approach with architecture specific code.

I plan to expose the UNIX Kernel Routing Table as a filesystem instead. Then do the routing protocols, and other actions like updating the table from information from other routers, and load-balancing etc from userspace scripts. The advantage is that, we will not need any daemons working directly on top of the kernel. Our simple userspace scripts that do the routing can hack on the, say /net/ether0/route  file.

One of the factors that will excite people will obviously be a awesome infrastructure to test new routing protocols in real networks, without writing complex architecture-specific daemons for GNU Zebra. Plus, I wonder what network mounts of such directories might lead us to achieve?!

UPDATE (May 03, 2009): Further discussion of this idea led to me applying to GSoC 2009 with this proposal. Although the idea was not selected, I got some valuable feedback and the project is still on (probably with a more relaxed timeline, and aligned towards Glendix rather than Plan 9 from Bell Labs).

DNS: A hard to crack nut!

Week 6 :-

Apparently, Linux kernel does not seem to have a DNS resolver! The fundtion gethostbyname() first checks /etc/hosts and if no entries are found, it makes a direct socket connection with the ip address given in resolv.conf and fetches the DNS resolved ip address!

I would do a in-kernel DNS implementation from scratch, but apparently, there are many issues with it. Its not so easy as it originally seemed! Read this response by a certain Josh Graessley in the MAC OS X community who understands Darwin probably. So did the Linux Kernel Hackers actually chose not to have DNS in-kernel for some real-world reasons?

More information we need, but a change of track in the project is apparent. We have decided to move on to the /net/tcp implementation and work with IPs for now.