DHCP is working, DNS servers in DHCP is not?

[Nate1749]

Ok, I am fairly new to this so I'm hoping it's something small...

In my server I have two 10/100 ethernet cards. One connects to my wirless router, which then connects to the internet, and the other connects to my wired hub. I have internet sharing enabled so that the wired-portion shares onto the wireless hub, which connects to my isp.

The router's ip is 10.10.10.21

The server has these two cards in it
10/100 card #1 (which runs to router) is 10.10.10.100
10/100 card #2 (which runs to hub) is 192.168.0.1

On the hub I have a computer, initially I manually assigned it ip, gateway, and dns (the machine is windows 98 by the way), and this worked fine. I could ping all the 10 & 192 addresses, and I could also browse the internet.

I then decided that I wanted DHCP set up for the hub, I set it up with the range of 192.168.0.2- .32, and connected the win 9x to the hub. On the win98 machine, I can ping all the 10 & 192 addresses, and I can ping yahoo's ip address, but when I type

http://www.yahoo.com

it's not working; so it seems to be the dns settings in dhcp. I have no dns settings in the tcp/ip properties for the windows 98 machine, I thought the dhcp server is supposed to handle that....

I do not have a DNS server setup, I am using the dns addresses that my isp told me to use for my router. What's throwing is off is that I thought the internet sharing maybe causing the problem, but then I remembered that when I manually assigned it the addresses that it worked fine.

Initially I had the DNS servers under scope options, but then just for the heck of it I moved it to server options. I've restarted the dhcp server, restarted the windows 98 machine serval times, I've also done ipconfig /release_all and /renew_all everytime I've made a change. I still receive the same results..... Do I have to do something special for dns to work in dhcp? Do I have to manually enter the ip of the dns in the settings (I don't want to do this, because this then ruins my idea of not having to configure)...

-Nate

 

[FaiTHLeSS]

Where/what is the DHCP running on? You will have to tell the DHCP server the DNS ip's it has to use on the network it wont work it out for itself.

 

[Nate1749]

DHCP is running on card #2, 192.168.0.1... The scope is 192.168.0.2-.32. That network however is sharing a network connection on the 10. address, which is actually connected to the internet.

Interestingly enough, just when I about gave up, it just started working. I disabled my firewall. I tried this before with no sucess, and I have in there that the 192.168.0.2, etc., addresses should all be ignored and not have firewall rules applied to them. ANyways, I just turned the whole firewall it off, restarted dhcp server, released and renewed on the win98 machine, tried to ping yahoo and it didn't work, then I tried again a few minutes later and now it works.

It seems that either the firewall rules (I'm running BlaceIce Server in paranoid mode) either don't take effect immeidately, or perhaps dhcp server needs a few minutes to actually reset itself (I actually always give it a minute and refresh it until it has been authorized).

Regardless, everything seems to be working now, but I'm not 100% sure why.

-Nate

 

[Nate1749]

Ok I've played around with it enough to notice some patterns, and I'd prefer to fix them....

1) My firewall has to be off, if I restart my win98 machine with the firewall on, then I will still receive an ip from the dhcp server on 192...1 and be able to ping my 192. addresses, but will time out when pinging my 10. addresses

2) If I have my firewall 100% off and I restart my win98 machine, I receive an ip from the dhcp server on 192...1, and am able to ping all 192 and 10. addresses. I am also able to ping the ip address of yahoo.com However, in order to actually ping yahoo.com, I have to wait exactly 5 minutes from when the lease of the ip is issued. I'm assuming there's an update interval somewhere for 300 seconds or something along those lines? Can I change this....

After I get this working, then I'll deal with the firewall problem..... I'm also trying to get some network shares, but under network neighboorhood I can only see the 10. addresses, no way to see the 192. addresses, is this easily changable or do I have to set up active directory?

-Nate

 

[GlenJohnson]

I have internet sharing enabled so that the wired-portion shares onto the wireless hub, which connects to my isp
If you mean ICS, you need to turn that off to use dhcp. ICS is a mini version of dhcp. Keep us informed, sounds like a good spy novel.

Glen A. Johnson
"To fear the worst oft cures the worse."
William Shakespeare (1564-1616); English dramatist, poet.

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[Nate1749]

I do mean ICS, but I can't turn it off or else I can't browse the internet through computers on my wired hub (which is the whole reason I have this setup).

See my goal was to have this setup isp -> wireless router (no dhcp here) -> server on card #1 with ip of 10.10.10.100 ..... Card #1 is sharing the connection to card #2, which is a 192.168.0.1 address, which is connected to -> wired 16 port hub. On this wired hub I wanted dhcp setup so that anyone could just plug in and they'd be online, assuming that the server was online.

However, if my server is off then you could either use the wireless portion or plug into the back of the wireless portion, but both would require setting up ip addresses, etc... I guess I was trying to have the portion that really sees the outside world be a bit more secure and the real internal portion be pretty open....


Anyways, above I said that if I turn my firewall off and restart I can ping 192, and 10, addresses; actually I was wrong. I can do that, but first I have to (after I restart) a ipconfig /release & /renew, and then I can ping all my local addresses and internet addresses and then 5 minutes later I can actually ping yahoo.com....

However, now that you've told me that ICS is essentailly a mini version of dhcp (which explains why when it changed the ip to 192.168.0.1; I don't like to use typical addresses even if they're internal, previously I had card #2 set to 192.168.10.21), it helps point a finger to some of the problems I'm having.

I set up dhcp about a year ago on another machine and it worked perfectly fine, that why I thought it was something small. Previously I wasn't using ICS though, now that I am, I think that's causing the problems.

What I don't get is it's sort of working, except I just have to do a /release, /renew, after I restart (then I can ping everything but domain names), then 5 minutes later I can ping domain names?? I could understand if it didn't work at all, but ....

-Nate