Hi all,
This is likely to get some comments about windoze but I'll wade in anyway...
Our internal dnscache either goes to sleep over night and is too slow to
respond first thing in
the morning, or some other behaviour is affecting the windows box when it first
starts and makes
internal domain lookups fail. I will endeavour to explain further...
I have a test server on our internal network that uses dnscache set up to
handle caching for our
windows XP machines. This works very well as a rule. The router/gateway to the
broadband is the
dhcp server and it dishes up the nameserver records and IP configuration as
follows:
C:\DATA>ipconfig /all
(some useless info removed)
Windows IP Configuration
Host Name . . . . . . . . . . . . : gm-n800c-60gb
Primary Dns Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No
DNS Suffix Search List. . . . . . : gmcs.internal
Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix . : gmcs.internal
IP Address. . . . . . . . . . . . : 10.1.1.100
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 10.1.1.1
DHCP Server . . . . . . . . . . . : 10.1.1.1
DNS Servers . . . . . . . . . . . : 10.1.1.90
203.2.75.132
198.142.0.51
Those last two dns servers are those of our ISP. They are there for when the
test server is not
available.
The domain gmcs.internal has a tinydns setup with all the usual stuff in it.
The dnscache
instance has an environment set to look locally for that domain. This works
fine except for
first thing in the morning.
So the symptom is that when I try to access a host on the internal network via
say ssh the
lookup fails with a "no host found" first time after the PC has been turned on.
The only way to
fix it is to use
c:/ipconfig /registerdns
from the command line. As soon as that command has been run, then the lookup
will succeed and
all is well.
So I am guessing that the "ipconfig /registerdns" is needed to stop windows
from remembering a
lack of response when it first powered up. It "seems" to me that windows is a
bit undisciplined
in its caching of negative and non-answers. Is this likely to be the case?
Are there any procedures I can run to determine if it is dnscache just falling
asleep overnight
and is too sluggish for windows liking?
Any ideas to help diagnose and resolve this would be appreciated.
Friendly digs welcomed <grin>.
Graham Miller
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