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DHCP problems with stale sessions

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typhoon52x

Technical User
Jul 15, 2003
44
GB
Hi,

Hope somebody can help as im stuck on this!
My setup is i have a Bt voyager router, and 4 client PC's connected to this via a network switch. The router is set to DHCP and all clients issued ip's from this

The problem has arisen for no apparant reason other than adding the 4th client 2 days ago.
Sometimes you cant get an internet connection or network connection, however if you goto ipconfig and release and then renew all works fine!
The problem is intermittant one day it will work others it wont, the dhcp list seems to keep clinets on it even tho they disconnected days before?

My ISP said it is due to 'stale sessions' and only support they could offer was to goto static IP's and disable DHCP on the router.

Any advice appreciated! All worked fine till 4th client added but that could be coincidence!
 
For such a small network the use of static IPs is not a bad one.

. Can you adjust the lease interval on the DHCP server in the router?

. if not, the advice given is likely the best you can obtain. See:
You could use either gpedit.msc (for XP Pro or Win2k clients) or Scheduled tasks to run a .bat or .cmd file at logon containing:

ipconfig /release
ipconfig /renew
 
hi, bcastner

yes i can adjust the lease interval on the DHCP it is set to 1day 0hours 0min would you recommend a different setting to resolve this problem?

 
That lease interval should not be posing an issue.
Check:

. that the DHCP scope is large enough. Allow for at least 50 entries;

. that the network adapter driver is completely up-to-date; if you can identify the chipset OEM manufacturer for the adapter, the website of the chipset manufacturer often has better drivers than the OEM of the adapter.

. there are no firewall issues blocking DHCP discovery.

If this is an XP client:

Start, Run, netsh int ip reset resetlog.txt

If this is an XP Service Pack 2 client, in addition do:
Start, Run CMD
netsh winsock reset catalog
 
thanks bcastner, have assigned static ips for a while then gone back to dhcp, and done what you mentioned above and all seems ok for now!

You mentioned allowing a range of 50 entries, i did have a range of 6 entries as the the DHCP server kept issueing ip's incrementally and constantly climbing! IP's that lease had expired days ago were not re-issued, this caused problems with my firewall as for security its set to accept only range 192.168.1.1 - 192.168.1.8 do you know how i can make the DHCP server issue IP's that have expired instead of using new higher ones?
 
spoke to soon!

was just browsing web then it said "cannot find page" on any site i tryed to browse.(tryed lots so wasnt a server down at the other end) However outlook express could get a connection???!!!?

did /release /renew and all worked fine again, the IP lease wasnt due to expire for another 4hrs?

any help appreciated, do you think its a problem with IE6?
Strange that it all works after a release /renew yet OExpress can get a connection all the time.

 
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