Re: Fresh (non cached) dig
On Mon, 5 Jan 2009, Stephen Ward wrote: > On Mon, 05 Jan 2009 16:24:04 +, Chris Thompson wrote: > > > On Jan 5 2009, John Wobus wrote: > > > >>[...] There is no nameserver > >>operation > >>that dig could do to tell a caching nameserver to act differently for > >>one query. You could clear the nameserver's cache, or even clear the > >>one name you are interested in out of the cache. > > > > You can use +norecurse and check whether the AA bit is set in the reply. > > Even quite old versions of BIND will not set the AA bit in the response > > if the answer is from the cache, in this case. > > Thanks for this Chris. I never knew that. And Todd, that is just what the > doctor ordered! Do some tests with data already cached. And watch the TTL of the records as you do multiple same digs. Jeremy C. Reed ISC Sales & Support Engineer ___ bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users
Re: Fresh (non cached) dig
On Mon, 05 Jan 2009 16:24:04 +, Chris Thompson wrote: > On Jan 5 2009, John Wobus wrote: > >>[...] There is no nameserver >>operation >>that dig could do to tell a caching nameserver to act differently for >>one query. You could clear the nameserver's cache, or even clear the >>one name you are interested in out of the cache. > > You can use +norecurse and check whether the AA bit is set in the reply. > Even quite old versions of BIND will not set the AA bit in the response > if the answer is from the cache, in this case. Thanks for this Chris. I never knew that. And Todd, that is just what the doctor ordered! -- . . . ___ bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users
Re: Fresh (non cached) dig
On Jan 5 2009, John Wobus wrote: [...] There is no nameserver operation that dig could do to tell a caching nameserver to act differently for one query. You could clear the nameserver's cache, or even clear the one name you are interested in out of the cache. You can use +norecurse and check whether the AA bit is set in the reply. Even quite old versions of BIND will not set the AA bit in the response if the answer is from the cache, in this case. -- Chris Thompson Email: c...@cam.ac.uk ___ bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users
RE: Fresh (non cached) dig
I've been doing some testing lately on query times. What I did was create a new zone and create a * record within it. Then, from a shell, I do "dig @server $RANDOM.test.testdomain.com". For more randomness, you can combine: "dig @server $RANDOM.$RANDOM.test.testdomain.com" That's how I've worked around the caching issue. I also set the TTL on the * record to be 1 second, to ensure that I don't hit any cache. Cheers, Todd. > > If you're referring to your local system's cache, you can bypass this > by specifying a DNS server for dig to query. use @dns.server.domain or > @4.2.2.2(for example) for this. > > If you're referring to the cache on the server you're trying to query, > sorry, that's beyond your control, unless you have root on that server. > > -wes > > On Fri, Jan 2, 2009 at 12:11 PM, Stephen Ward < > stephen.usenet.w...@wibblywobblyteapot.co.uk> wrote: > >> For all my attempts to read the manual on DIG I can't find a way to >> do something really simple. >> >> Is there a way to dig a domain name so even if the results are in >> cache, it will ignore these and re-read them? It's really from a >> testing perspective I'm looking at this. I can mash the keyboard each >> time to try and get a better handle on the query time, but there has >> got to be an easy way to do this? >> >> >> >> -- >> . . . >> ___ bind-users mailing >> list bind-users@lists.isc.org >> https://lists.isc.org/mailman/listinfo/bind-users >> >> > --=_Part_21674_19533272.1230941795123 Content-Type: text/html; > charset=ISO-8859-1 Content-Transfer-Encoding: 7bit > Content-Disposition: inline > > If you're referring to your local system's cache, you can > bypass this by specifying a DNS server for dig to query. use > @dns.server.domain or @http://4.2.2.2";>4.2.2.2 (for > example) for this.If you're referring to the cache on the > server you're trying to query, sorry, that's beyond your > control, unless you have root on that server. -wes class="gmail_quote">On Fri, Jan 2, 2009 at 12:11 PM, Stephen Ward > < href="mailto:stephen.usenet.w...@wibblywobblyteapot.co.uk";>stephen.usene t.w...@wibblywobblyteapot.co.uk> > wrote: For all my attempts to read the manual on DIG I can't find a > way to do something really simple. Is there a way to dig > a domain name so even if the results are in cache, it will ignore > these and re-read them? It's really from a testing perspective > I'm looking at this. I can mash the keyboard each time to try > and get a better handle on the query time, but there has got to be > an easy way to do this? > -- . . . ___ > bind-users mailing list href="mailto:bind-users@lists.isc.org";>bind-users@lists.isc.org > https://lists.isc.org/mailman/listinfo/bind-users"; > target="_blank">https://lists.isc.org/mailman/listinfo/bind-users > > > --=_Part_21674_19533272.1230941795123-- > > --===3579383764054783402== Content-Type: text/plain; > charset="us-ascii" MIME-Version: 1.0 > Content-Transfer-Encoding: 7bit > Content-Disposition: inline > > ___ bind-users mailing > list bind-users@lists.isc.org > https://lists.isc.org/mailman/listinfo/bind-users > --===3579383764054783402==-- I had a feeling forcing lookups against other servers was all I could do. Problem is, once you've done that it's cached there too. Not a major issue, just wanted to be sure it was not easily doable. -- . . . ___ bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users - This transmission (including any attachments) may contain confidential information, privileged material (including material protected by the solicitor-client or other applicable privileges), or constitute non-public information. Any use of this information by anyone other than the intended recipient is prohibited. If you have received this transmission in error, please immediately reply to the sender and delete this information from your system. Use, dissemination, distribution, or reproduction of this transmission by unintended recipients is not authorized and may be unlawful. ___ bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users
Re: Fresh (non cached) dig
I'm imagining you want a way to make dig act like the caching nameserver and do what it would do and show you the answer. dig +trace does something similar to this. There is no nameserver operation that dig could do to tell a caching nameserver to act differently for one query. You could clear the nameserver's cache, or even clear the one name you are interested in out of the cache. Sometimes querying another name in the domain you are interested in is sufficient for whatever you are checking. In certain situations, it can be very helpful to check someone else's caching nameserver, so it is helpful to have a few such addresses on hand. These days, a lot of sites are closing their caching servers (go figure!), and I've been using OpenDNS's servers. On Jan 2, 2009, at 8:11 PM, Stephen Ward wrote: For all my attempts to read the manual on DIG I can't find a way to do something really simple. Is there a way to dig a domain name so even if the results are in cache, it will ignore these and re-read them? It's really from a testing perspective I'm looking at this. I can mash the keyboard each time to try and get a better handle on the query time, but there has got to be an easy way to do this? -- . . . ___ bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users ___ bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users
Re: Fresh (non cached) dig
On Fri, 02 Jan 2009 16:16:35 -0800, wes wrote: > --===3579383764054783402== Content-Type: > multipart/alternative; > boundary="=_Part_21674_19533272.1230941795123" > > --=_Part_21674_19533272.1230941795123 Content-Type: text/plain; > charset=ISO-8859-1 Content-Transfer-Encoding: 7bit > Content-Disposition: inline > > If you're referring to your local system's cache, you can bypass this by > specifying a DNS server for dig to query. use @dns.server.domain or > @4.2.2.2(for example) for this. > > If you're referring to the cache on the server you're trying to query, > sorry, that's beyond your control, unless you have root on that server. > > -wes > > On Fri, Jan 2, 2009 at 12:11 PM, Stephen Ward < > stephen.usenet.w...@wibblywobblyteapot.co.uk> wrote: > >> For all my attempts to read the manual on DIG I can't find a way to do >> something really simple. >> >> Is there a way to dig a domain name so even if the results are in >> cache, it will ignore these and re-read them? It's really from a >> testing perspective I'm looking at this. I can mash the keyboard each >> time to try and get a better handle on the query time, but there has >> got to be an easy way to do this? >> >> >> >> -- >> . . . >> ___ bind-users mailing list >> bind-users@lists.isc.org >> https://lists.isc.org/mailman/listinfo/bind-users >> >> > --=_Part_21674_19533272.1230941795123 Content-Type: text/html; > charset=ISO-8859-1 Content-Transfer-Encoding: 7bit > Content-Disposition: inline > > If you're referring to your local system's cache, you can bypass > this by specifying a DNS server for dig to query. use @dns.server.domain > or @http://4.2.2.2";>4.2.2.2 (for example) for > this.If you're referring to the cache on the server > you're trying to query, sorry, that's beyond your control, > unless you have root on that server. -wes class="gmail_quote">On Fri, Jan 2, 2009 at 12:11 PM, Stephen Ward dir="ltr">< href="mailto:stephen.usenet.w...@wibblywobblyteapot.co.uk";>stephen.usenet.w...@wibblywobblyteapot.co.uk> > wrote: For > all my attempts to read the manual on DIG I can't find a way to > do something really simple. > > Is there a way to dig a domain name so even if the results are in > cache, it will ignore these and re-read them? It's really from a > testing perspective I'm looking at this. I can mash the keyboard > each time to try and get a better handle on the query time, but > there has got to be an easy way to do this? > > > > -- > . . . > ___ bind-users mailing > list > href="mailto:bind-users@lists.isc.org";>bind-users@lists.isc.org > https://lists.isc.org/mailman/listinfo/bind-users"; > target="_blank">https://lists.isc.org/mailman/listinfo/bind-users > > > --=_Part_21674_19533272.1230941795123-- > > --===3579383764054783402== Content-Type: text/plain; > charset="us-ascii" MIME-Version: 1.0 > Content-Transfer-Encoding: 7bit > Content-Disposition: inline > > ___ bind-users mailing list > bind-users@lists.isc.org > https://lists.isc.org/mailman/listinfo/bind-users > --===3579383764054783402==-- I had a feeling forcing lookups against other servers was all I could do. Problem is, once you've done that it's cached there too. Not a major issue, just wanted to be sure it was not easily doable. -- . . . ___ bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users
Re: Fresh (non cached) dig
Stephen Ward wrote: > For all my attempts to read the manual on DIG I can't find a way to do > something really simple. > > Is there a way to dig a domain name so even if the results are in cache, > it will ignore these and re-read them? It's really from a testing > perspective I'm looking at this. I can mash the keyboard each time to try > and get a better handle on the query time, but there has got to be an > easy way to do this? What are you trying to measure? If you're trying to measure the query time from the resolving name server to the authoritative name server, run dig on the host running the resolver and query the authoritative host directly. If you're trying to measure the query time between you and the resolver, you don't care if the answer has been cached or not. hth, Doug ___ bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users
Re: Fresh (non cached) dig
If you're referring to your local system's cache, you can bypass this by specifying a DNS server for dig to query. use @dns.server.domain or @4.2.2.2(for example) for this. If you're referring to the cache on the server you're trying to query, sorry, that's beyond your control, unless you have root on that server. -wes On Fri, Jan 2, 2009 at 12:11 PM, Stephen Ward < stephen.usenet.w...@wibblywobblyteapot.co.uk> wrote: > For all my attempts to read the manual on DIG I can't find a way to do > something really simple. > > Is there a way to dig a domain name so even if the results are in cache, > it will ignore these and re-read them? It's really from a testing > perspective I'm looking at this. I can mash the keyboard each time to try > and get a better handle on the query time, but there has got to be an > easy way to do this? > > > > -- > . . . > ___ > bind-users mailing list > bind-users@lists.isc.org > https://lists.isc.org/mailman/listinfo/bind-users > ___ bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users
Fresh (non cached) dig
For all my attempts to read the manual on DIG I can't find a way to do something really simple. Is there a way to dig a domain name so even if the results are in cache, it will ignore these and re-read them? It's really from a testing perspective I'm looking at this. I can mash the keyboard each time to try and get a better handle on the query time, but there has got to be an easy way to do this? -- . . . ___ bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users
