After a year of heavy linux I was beggining to feel relatively confident. I had not had a serious system problem in months. However today I noticed that a client was not recieving an internet feed from a NAT'ing server. I checked the server and sure enough both the internal and external interfaces were down. Infact they werent even "inactive". I could not ifconfig them back up because they were not being detected nor could I manually identify them.
I checked the man pages to see where the scripts were that held the interface configurations but I could not find any that seemed to specifically link an interface to an address or alias.
Looking back ... ever since instally rh9 on the server the interfaces have been somewhat funny. Origionally upon automatic configuration during os install the internal was labeled eth1 and extiff eth0. This offended me so I switched. RH9 did not like this and i have to fight with it to keep both eth1 and eth0 up simultaneously. Then all was okay for several weeks. UNtill now. Perhaps my switching these alias names contirbuted to this matter.
Upon install today the interfaces were detected eth1 extiff , eth0 intiff. I repeated trying to switch them and again rh resisted. So i gave in and kept the system defaults and changes my masquerading and iptable scripts.
My question is what should i have done to trouble shoot this. At the time i did not even consider the iface switching issue but i realized it after the second full install.
What do you do when this sort of thing happens.

Thanx

i menat that intiff were detected as eth0 and intiff eth1
sorry