Re: Router

Steven Pampling <steve.pampling@xxxxxxxxxxxxx> wrote:
In article <49f*pOFkr@xxxxxxxxxxxxxxxxxxxxxxxxxxx>, Theo Markettos
<theom+news@xxxxxxxxxxxxxxxxxxxxxx> wrote:
Note also in this case it's inadvisable to power down the router without
all the other machines being powered down first. It won't damage
anything, but when the router is switched off it forgets which IP
addresses it has handed out. When switched on again it might hand out
an address that's it gave another machine before being switched off,
which could cause a clash.

Machines using DHCP *properly* deal with this situation.

How does this work? My understand was that DHCP hands out a 'lease' for a
particular IP address, which means the machine checks out an IP address for
that period of time then, when the lease has expired, it has to check back
in to the DHCP server to receive a new IP address (which might be the same
one as before). If the DHCP server is rebooted, how do the machines know
their address has been invalidated until they renew their lease?

Ah, right, it seems the server can invalidate all clients by broadcasting a
DHCPNAK message. This doesn't seem to be mandated in the specification - do
servers actually do this when they boot up?

Theo
.

Relevant Pages

  • Re: IP numbers
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  • Re: Phantom DNS server
    ... Dilan Weerasinghe made a post then I commented below ... >> On the ipconfig for the machines with the bogus DNS address, ... > They show the correct DHCP server. ...
    (microsoft.public.win2000.dns)
  • Re: Duplicate reverse lookup entries/nslookup problems
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    (microsoft.public.windows.server.dns)
  • Re: DHCP and clients
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    (microsoft.public.windows.server.sbs)
  • Re: <>
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    (microsoft.public.windows.server.dns)