Hello,
I had bought this month's Digit magazine which had 3 distro ISOs in one DVD. OpenSuse, Fedora11 (live+Install) and Ubuntu 9.04 (Live+Install). Thankfully, the ISOs did not throw up any md5sum errors.
First the Fedora live cd was booted. Everything came up fine. I checked out the /etc/sysconfig/network-scripts folder to check out the ifup-eth0 file but was surprised to see that there was no such file. The command ifconfig threw up the eth0 details. The networking was taken over by 'Network-Manager', the gui utility for gnome. Then Firefox was tried out. It was 3.5 Beta4. Sites opened lightning fast. Out of curiosity I checked out the dns entries in resolv.conf and saw the following DNS server entries (using dhcp). 59.185.0.23 and 59.185.0.50. Then I logged into my MTNL Triband modem to discover that I had earlier disabled DNS relay and my preferred DNS servers were the 203.94..... entries. In the modem's interface however, the DNS is 59.183.63.254. I wonder how 59.185.0.23 got into the DNS entries of the computer. However I am happy as these servers seem to be very quick.
The Ubuntu 9.04 cd was then booted and even here the DNS entries were 59.185.0.23 and 50. Again, the sites opened very fast. As with Fedora11, the /etc/network/interfaces file had only one entry for lo. There was no entry for eth0.
The observations made were.
1. MTNL's new DNS servers 59.185.0.23 & 50 are very fast and those entries should replace the traditional 203.94... entries in machines with static ips. Before this, at 2 of my clients' places I had to use the open dns ip as the secondary dns entry for sites to open at least. Now I can try out these new IPs.
2. The gui networking utilities have completely taken over the traditional distro network config files and we don't even know how these GUIs are storing their config files to be able to read/modify them. I recollect, before throwing out knetwork-manager from my Lenny, I had a tough time trying to locate the config files for the same and even googling did not help.