What does DNS - > Reload from master do ?

[DeeVeeDee]

What does "Reload from Master" do when i right click one of the forward lookup zones and select
Reload from master ?

whats it the difference between

Reload
Transfer from master
Reload from master ?

Our DNS comes to a stand still only on one of the forward lookup zones which are all the DNS entries for intranet sites in a different country.
When i click reload it solves the problem. But sometimes this happens at night and i can upload financial data to our mother company cus it cant find a hostname.

[rustypup]

aaargh! you've killed the internets!

reload flushes and initialises from the local cache..

transfer results depend on the transfer setup... if full zone, you get everything, if incremental, deadwood may remain...

reload from master attempts a flush before transfer... so, full snapshot regardless of transfer setup - at least, according to my sketchy knowledge...

[DeeVeeDee]

Hehe luckily our DNS is not public and is only used internally to reach some intranet sites in europe.

when i reload it fixes the problem (I dont know how it fixes the issue but it does)
When i reload from master it breaks and DNS does not respond to any requests from the PC's in our LAN until i do a normal reload again.

So am i correct in assuming the DNS server automatically reloads from master on a scheduled basis ? defenitly not daily cus the problem only occurs on a regular once in a while basis.

I tried to ping the master and it replies

[rustypup]

firstly, if it's behaving like reload from master, your transfer policy is full zone, (AFXR), as opposed to incremental, (IFXR)

secondly, if the transfer is scribbling routes, spend some time analysing the before and after SRV and glue mappings.... something hinky going on there....

if a local reload is "sorting" the issue, i'm stumped and would refer you to someone like Nuke... who eats this stuff like the anguished souls of smurfs...

[DeeVeeDee]

I think when i reload its reloading from its own cache, but when loading from its master it cant for some reason.
I just dont know why it goes "Offline" when it cant load from the Master. It should just carry on serving from its local cache.
also it does not log anything into the event viewer.

[rustypup]

"reload from master" trashes whatever is in open cache first, and then attempts to grab the entire zone from master... reload will grab from the local .dns file cache....

if the master is not serving, you're not getting... could be the master doesn't share the name server love with your box? have you tried to load the stub?

[DeeVeeDee]

Stub?

Normally the event log will show a red stop sighn if there's an error i found the following error
in one of the notification messages with the blue "i" on it.

The DNS server has completed a scavenging cycle but no nodes were visited. Possible causes of this condition include:

1) No zones are configured for scavenging by this server.
2) A scavenging cycle was performed within the last 30 minutes.
3) An error occurred during scavenging.

The next scavenging cycle is scheduled to run in 168 hours.

The event data will contain the error code if there was an error during the scavenging cycle.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

168 hours which is 7 days, i would say is about when this problem occurs.
When i changed the DNS file to something new the eventlog say it dumped a version called 20091205 which i assume is the last time it actually updated from the master.

[rustypup]

have you run nslookup on the master recently?

a stub zone == SOA and NS records only... while the master may bounce your AXFR request, it should still permit you to pull the stub data without interference...

[DeeVeeDee]

if i run nslookup and use the master's hostname it "hops" via the local one and shows the master's hostname and IP.
But this doesnt mean it queried the master it found the masters name in the local DNS cache.

I'm starting to think something on our firewall changed.
Is there a utility i can use to query a remote DNS server ?
So that i can try and query the Master DNS, cus i dont have access to it via RDP and its sitting in europe.

[rustypup]

Code: Select all

nslookup
>set type=ns
>[master's domain name]

this should respond with all the name servers in their domain, any one of which will allow you to create a local stub..

if the domain doesn't reconcile, the problem is definitely homegrown...

[DeeVeeDee]

Ok it returned their name servers fine.

Let me try and create a stub or atleast change the current forward lookup zone to a stub

EDIT
****Oh my Goooooodnesssss****

Now it only has a few entries! all its sub folders are gone

[DeeVeeDee]

Ok now i understand what is happening i still dont know what is wrong!!!!! but atleast your help has solved the issue for now.

The faulty forwardlookup zone's DNS entries are the only ones that is not available when it tries to "scavenge" new DNS entries from the Master.
But reloading it loads from a previous successfull saved DNS cache which is still separate from the domain.local zone.

changing the faulty one to a stub reconciled the fault zone's current entries with the local domains zone database.
therefore it cleared the faulty forward zones database. and will only ever have something in there when i manage to get it working again.

But at least now its entries is saved into the Active directories DNS.

Very kewl!

Thanks allot man. you saved the day.

[rustypup]

a stub is SOA and name servers only.... it will not provide host records, but will give you non/authoritative name servers into the stub'd domain... higher traffic, but certainly fewer faults...

depending on your relationship with the external company, you may want to negotiate to have your primary DNS server added into their trust roll for updates... then you can revert to IXFR + after hours AXFR on their primary...

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