I assign resellers 2 IPs to start with: 1st IP is domain.com and ns1.domain.com. 2nd IP is ns2.domain.com. Is there any reason why I can't or shouldn't assign thru WHM the second IP as their resold accounts shared IP as well? Seems this would help prevent the main shared IP and other resellers from going down if there is a ddos attack on an IP. Only the reseller (and clients)with that IP would be down.
It's another step in determining who is being attacked, at least to the reseller level, instead of not knowing where to begin if everything is on the main shared IP. This may have been discussed before, but I couldn't find anything on it. Thanks

Are the IPs on different machines?

If not, it will have no difference if you're DOSed on one or IP or the other, your whole box is going down. It would possibly make tracking easier though, I suppose.

Not always true.... I still have a box that is split with another host, and it underwent a ddos attack. All the sites with dedicated IPs stayed up, just the IP (main shared IP) under attack was nullrouted until the attack was over. I could get to all sites except for the shared accounts. This is why I am wondering if I can protect the rest of my servers this way. Is there any ill affects in assigning a nameserver IP as a shared IP? (Other than the main one)

If you nullroute the IP, of course the other sites will work.

But before that happens the entire box is going to be hit.

There are no bad affects from doing what you want to do as far as I know. I'm pretty sure that's how I have mine set up and it works fine.

I understand. I thought you were saying they would yank the box from the network. Yes, initially, until the IP is nullrouted, the whole box...and network...is affected.
Thanks for the response.