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Old 04-20-2003, 01:27 AM   #16
MetaPhyzx
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Glad that seems to be working out for you...insofar as a good book on DNS; I cant readily recommend one for you, but take a look at the Linux Documentation project, there should be a decent how-to in there someplace.
 
Old 04-20-2003, 04:54 PM   #17
Eric Pratt
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Hmmm, I set my default lease time to 86400 seconds (a day), and now it's the next day and when the lease expired, it didn't get a new one and lost connection to the intra and internet. What am I missing here? Should I just crank my lease time up to a year?
 
Old 04-20-2003, 04:56 PM   #18
david_ross
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Why not give them fixed leases or even fixed IP's.
 
Old 04-20-2003, 05:29 PM   #19
MetaPhyzx
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Ok..these workstations are "generic" Windows installs, correct? but this also stands out in the info you sent, I didnt catch it before:

option routers 172.168.0.0

assuming these workstations have a default gateway, this appears to point to the network address of the subnet you're using. (network address is the first addy in a subnet, and is unusale, and the broadcast address is the last in a subnet, also unusable) That may have nothing to do with it... but hey.

With DHCP, since they appear to get an address after a reboot, correct? Then there isnt a problem with the DHCP requests reaching the DHCP server.

If thats the case, your issue probably isnt with the workstations. Do a "ipconfig /renew" (if that applies to the operting system you're using) on the workstation and see if it is issued a new IP.

I'm still thinking ARP issue. If you have managable switches (Cisco's et.al) take a look at the switch ARP table. Take a look at the workstations arp tables (arp -a at the command line). I'm willing to bet some kind of caching of ARP entries is going on, and until that NIC card in the workstation goes down off the wire and forces some kind of ARP update it continues.


I'm stabbing in the dark here, cause usually what is broke is what has changed. You start chasing too much, you may create an issue.
 
Old 04-21-2003, 12:23 PM   #20
Eric Pratt
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The only machines having this problem are the w2k machines, the xp machines seem to be getting new leases when their time is up.
If the lease expires it does not get a new one, if I try ipconfig /renew it reports back that it can't reach the DHCP server. If I reboot the machine it picks up a new lease and it's good for another day.
arp -a reports back (while the lease is active):
Interface 172.168.0.100 on Interface 0x1000003
Internet Address Physical Address Type
172.168.0.0 00-04-5a-45-ac-04 dynamic
We don't have a Cisco router anymore, we ditched with the T1 line when we moved our servers out of the office, we just use a hub. I know this isn't really a Linux question anymore per se, but I do appreciate any help.
Thanks,
 
Old 04-21-2003, 12:35 PM   #21
MetaPhyzx
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Not a problem. Just so happens networking is what I do =) Now if I can get a firm grip on SQL and PHP...

try this: next time this problem occurs, clear the ARP Cache on the workstation. I can't remember the exact command (arp -r or something). then an ipconfig renew

But what may be happening is W2K is the caching culprit. When the 255.255.255.255 broadcast goes out to renew the address, W2K already has an ARP entry for whatever the DHCP server is. when you reboot, you clear the cache on that side. I'm sure theres a way to edit arp caching on the W2K box. you're sure you have a repeater (hub) and not a switch?
 
Old 04-21-2003, 03:18 PM   #22
Eric Pratt
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Okay, before the lease expires arp says is:
Interface 172.168.0.90 (the address via DHCP)
172.168.0.91
172.168.0.99 (two other computers it talks to)

After the lease expires arp says:
Interface 169.254.87.191 (a seemly random address)
172.168.0.91
And IPConfig says it's lost it's gateway and DNS (previously 172.168.0.0 and 206.13.29.12 respectively)
after deleting the arp entries (arp -d*) and trying ipconfig /renew I get the same error DHCP server unavailable and arp says No ARP Entries Found. I tried to manually enter the entry for the controller but I'm not getting something right.
I'm pretty sure I'm using a hub, it's a small linksys. Our traffic internally isn't much so I didn't think we'd need a switch.
Any thoughts?
 
Old 04-21-2003, 03:49 PM   #23
MetaPhyzx
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LOL!
*kicks himself*
Its trying to give itself an address. My Mac's used to do that all the time. It's ARP related; try the ARP table on the DHCP server, or the gateway/router

Take a look at this link:

http://ntcanuck.com/tq/TQ_Page4.htm#Item_112

and find "DHCP" on that page. I think thats your answer.

Last edited by MetaPhyzx; 04-21-2003 at 03:51 PM.
 
Old 04-21-2003, 11:04 PM   #24
Eric Pratt
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That's one from left field. Well, I disabled the APIPA but it still isn't picking up a new lease when it's lease expires. Is there any problem with giving the computers like, a six year lease? I mean I don't reset my computers often, but at least once a month.
 
Old 04-21-2003, 11:14 PM   #25
MetaPhyzx
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You may as well hardcode them if you're looking to do that. Somehow, you're in the middle of a wire problem that only a hardcode can work around. It's a viable workaround. But make sure you document it

Last edited by MetaPhyzx; 04-21-2003 at 11:18 PM.
 
  


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