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I'm sorry I can't offer any solutions, but I'll note that we
experienced similar problems last month when we attempted to upgrade
from dhcp 3.1.0 to version 4.1.0 running on Solaris 10. We ended up
reverting to version 3.1.0 after about 2 days, so I didn't gather a lot
of data. We're running in a single server environment, with no
failover configured.<br>
<br>
We experienced two notable issues:<br>
<br>
1) Assigning a static address to a formerly-dynamic client caused DHCP
services to stop responding, as detailed by Barry.<br>
2) Many statically-defined clients on the same network as the DHCP
server could cause services to hang, simply by a DHCPREQUEST (renew
lease). We found that these were frequently Macintosh systems,
although as I said, we didn't stay at version 4.1.0 long enough to
gather a lot of data.<br>
<br>
When we encountered our problems, the dhcpd daemon would continue to
run, but simply didn't seem to be responding to requests. At one
point, when the daemon was failing to respond to requests, I noted in
the logs that it rotated out the dhcpd.leases file as part of its
normal hourly operation. So it was still performing <i>some</i>
functions.<br>
<br>
Although I was able to write a script to run through cron to watch for
DHCP services becoming unresponsive (ie, watch for lack of updates to
the dhcpd.log file) and programmatically restart services, this didn't
resolve the problem of formerly-dynamic clients picking up newly
assigned static addresses. So we reverted back to version 3.1.0.<br>
<br>
Jane Zuzek<br>
<br>
Dean, Barry wrote:
<blockquote
cite="mid:D1349AE6C65B924FB0E5571C3E5AA130389D8DB4@STAFFMBX1.livad.liv.ac.uk"
type="cite">
<pre wrap="">I am still having the occasional problem with DHCP ceasing to answer requests from clients.
I have traced it to a reproducible situation.
Client (only seen with Linux and HP Printers at the moment) is sitting on a dynamically allocated IP from the pool and all is happy.
We allocate a fixed IP to the MAC address by editing in a "host {}" entry into the config and restart the master and slave server in the failover pair.
Client does a DHCPREQUEST for the dynamic IP, the server issues a DHCPNAK.
The client and server are on separate subnets with Cisco 6905E routers doing the dhcp relaying.
The interesting thing is that I see lots of DHCPNAKs, most do not cause a problem. Looking in the logs the "safe" NAKS look like:
DHCPNAK on <client IP> to <client MAC> via <router IP>
But the server stops serving clients as soon as it issues a NAK that is logged as:
DHCPNAK on <client IP> to <client MAC> via e1000g0
e1000g0 being the interface on the DHCP server (a Sun X4200).
This looks like DHCPD had broadcast the NAK instead of unicasting it to the router for relaying. The upshot is that the client does not see the NAK and keeps on using the dynamic IP it has.
This is causing us a bit of trouble at the moment as we have printers and PCs being moved all over the shop and we are losing the DHCP service several times a day.
What makes the server broadcast the NAK on its own local subnet? How can I stop it? I looks like a client issue, but the server's way of dealing with it is a cause for concern...
As the leases on our dynamic pools are 8 days, it can be a while after you issue the fixed address that the server dies. If it happens over a weekend we lose services. Our wireless access points seem particularly sensitive and we have lost wireless everywhere on one occasion.
Any ideas, I am getting hassle over this! Any help much appreciated.
Thanks.
---------------
Barry Dean
Networks Team
Computing Services Department
Tel: 0151 794 5641 (x45641), Web: <a class="moz-txt-link-freetext" href="http://pcwww.liv.ac.uk/~bvd/">http://pcwww.liv.ac.uk/~bvd/</a>
---
Nice boy, but about as sharp as a sack of wet mice.
-- Foghorn Leghorn
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</pre>
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