DNS record query

  • Thread starter Thread starter Daniel Tan
  • Start date Start date
D

Daniel Tan

Recently i discovered that when my dns service provider (local
company) is down but i still able to resolve the host name to ip and
vice versa (ping) but only thing is just don't have the 4 replies. How
come ? Does my isp have those records also ? Thanks.

Regards,
Daniel
 
Recently i discovered that when my dns service provider (local
company) is down but i still able to resolve the host name to ip and
vice versa (ping) but only thing is just don't have the 4 replies. How
come ? Does my isp have those records also ? Thanks.
Click to expand...

The above implies that either you client is resovling from it's
OWN cache of DNS entries or from an INTERNAL DNS
server but the ROUTING is actually down to your ISP.

You can resolve the name but actual connections are failing.

ALL IP connections are really by IP addresses.
 
Martin, can my isp capture the dns record and loaded into their dns
cache somehow through their router ? Thanks.

Regards,
Daniel
 
Martin, can my isp capture the dns record and loaded into their dns
cache somehow through their router ? Thanks.
Click to expand...
]
No. But your question presupposes some misunderstanding
of DNS so perhaps if we clear that up then we can help with
what you want... [Call me Herb]

DNS records aren't "loaded into routers" -- Routers and Routing
are about IP (only using addresses) packets being routed to
and from services and clients.

Analogy: Routing is like the postman and post office, actually
since letters have names and not pure addresses, routing is closer
to what a PHONE Switch does when you place a telephone call
by ONLY using a number.

DNS is like "operator assistance" or 411 service. You first use
the name to obtain the number (phone or IP) and then place the
call (or send the request.)

Also note that ISP's can't really "Load your DNS records".

The only ways that DNS server "load addresses" is through:

1) Having a zone for those records (being authoritative)
2) Caching (keeping) previous resolutions from earlier requests

You might then ask, "Can we create a Zone for my records?"
Not usually, since no one else will ask the ISP DNS for those records
unless YOUR ZONE is delegated to them from the parent.

Now, if your ISP is holding your Zone, that is precisely what is done.
In that case, the fact that the ISP is running the DNS is pretty much
incidental (anyone reliable and available) can run your DNS -- I could
even run it for you.

But then, that zone is YOUR ZONE -- the value of having the ISP do
this is that they will be PUBLICLY accessible and relieve you of this
duty -- Registrars are even better for this purpose most of the time,
e.g., Register.Com

Notice: It only makes sense to include PUBLIC addresses in a PUBLIC
DNS server -- adding addresses for 10-nets, 192.168.x.y, or the 127.16+
range won't work on THE Internet.




-----------------
The above implies that either you client is resovling from it's
OWN cache of DNS entries or from an INTERNAL DNS
server but the ROUTING is actually down to your ISP.

You can resolve the name but actual connections are failing.

ALL IP connections are really by IP addresses.
Click to expand...
[/QUOTE]
 
Herb, thanks for help. Btw how to view the local cache resolved dns
host name entries ?

Regards,
Daniel

Herb Martin said:
Martin, can my isp capture the dns record and loaded into their dns
cache somehow through their router ? Thanks.
Click to expand...
]
No. But your question presupposes some misunderstanding
of DNS so perhaps if we clear that up then we can help with
what you want... [Call me Herb]

DNS records aren't "loaded into routers" -- Routers and Routing
are about IP (only using addresses) packets being routed to
and from services and clients.

Analogy: Routing is like the postman and post office, actually
since letters have names and not pure addresses, routing is closer
to what a PHONE Switch does when you place a telephone call
by ONLY using a number.

DNS is like "operator assistance" or 411 service. You first use
the name to obtain the number (phone or IP) and then place the
call (or send the request.)

Also note that ISP's can't really "Load your DNS records".

The only ways that DNS server "load addresses" is through:

1) Having a zone for those records (being authoritative)
2) Caching (keeping) previous resolutions from earlier requests

You might then ask, "Can we create a Zone for my records?"
Not usually, since no one else will ask the ISP DNS for those records
unless YOUR ZONE is delegated to them from the parent.

Now, if your ISP is holding your Zone, that is precisely what is done.
In that case, the fact that the ISP is running the DNS is pretty much
incidental (anyone reliable and available) can run your DNS -- I could
even run it for you.

But then, that zone is YOUR ZONE -- the value of having the ISP do
this is that they will be PUBLICLY accessible and relieve you of this
duty -- Registrars are even better for this purpose most of the time,
e.g., Register.Com

Notice: It only makes sense to include PUBLIC addresses in a PUBLIC
DNS server -- adding addresses for 10-nets, 192.168.x.y, or the 127.16+
range won't work on THE Internet.




-----------------
"Herb Martin" <[email protected]> wrote in message
Click to expand...
Click to expand...
 
Herb, i can't find advanced in the menu. Any command to view the
cached dns entries ? THanks.

Regards,
Daniel
 
Daniel Tan said:
Herb, i can't find advanced in the menu. Any command to view the
cached dns entries ? THanks.
Click to expand...

You are running the DNS MMC, right?

dnsmgmt.msc (you can just hit WinKey-R and type dnsmgmt.msc if you
get tired of all those menus)

You see the VIEW menu? (inner frame)
(To the right of Action, underneath Console & Window on the outer frame)

If View\Advanced is NOT checked, then select it -- you get the cache
(and maybe some other stuff)
In the MMC GUI choose Menu View\Advanced.

Viewing the cache is considered an "Advanced" option.
Click to expand...
[/QUOTE]
 
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