7 replies to this topic

[Piotr GRD]

In the future, if one of you has a intermittent DNS issue and is technically inclined, try installing dig in a UNIX environment and compare the results of:

CODE

dig @ns1.heliohost.org yourdomain.com
dig @ns2.heliohost.org yourdomain.com

If the results are different (especially if one of the results does not exist), then we have a problem.

And even not inclined technically people that don't know what the DIG is and how to use it, can use this online utility that I have created 2 days ago especially for this purpose:
HelioHost DNS Checker (DIG) - http://heliohost.grd.net.pl/dns-checker/
It will let you query both HelioHost nameservers with just one click. Highlighted "answer section" should be the same on both servers - if not, then as djbob wrote: problem.

[Krydos]

Split this topic from it's original location, posted it here, and pinned it here next to Piotr GRD's server monitor so it will be easier to find.

Thank you for all your great contributions.

[cl58]

I'm a little confused. Is this any different from Byron's DNS checker?

[Piotr GRD]

Yes.

Byron's utility let you check these DNS records that entire internet sees. He is most likely using the results returned by dns_get_record() function.

My utility checks the DNS records on ns1.heliohost.org and ns2.heliohost.org specifically. This may be different than what entire internet sees, ie. if one does not use HelioHost nameservers as authoritative for the domain name. I am using DIG to query these nameservers. It's something like http://www.spacereg.com/a.rpl?m=dig or http://www.kloth.net/services/dig.php but without possibility to select specific records or custom nameservers. It's designed to check only records on both HelioHost nameservers as quickly as possible - with one click.

My tool will be useful in a case of some problems with HelioHost nameservers. Two times already ns2 did not return any records for some of the domains while ns1 did (nameservers were not synchronised). Now anyone, even someone that don't know what the DIG is, can diagnose such problem very quickly.



Check "grd.net.pl" for example. This domain is NOT parked on HelioHost, so obviously HelioHost nameservers does not have any records about it. My tool will show that there are no records for this domain on ns1/ns2.heliohost.org. Byron's tool will display you what the entire internet sees, that domain name is pointed to dns/dns2/dns3.home.pl (my registrars nameservers).

Check "google.com". Now here you'll be surprised. ; ) Someone did point this domain name to some account on Stevie and using my tool you'll find that HelioHost nameservers points "google.com" to IP 216.218.192.170. This is obviously NOT what entire internet sees, Google does not use HelioHost nameservers as authoritative so records in here does not matter at all, google.com is not served from Stevie for anyone that use public DNS system.
edit: Not anymore, records for "google.com" has been deleted on HelioHost nameservers.

[Krydos]

I like this tool because I don't have to open two tabs and type the same domain into both and then check ns1.heliohost.org in one tab and ns2.heliohost.org in another tab. You can do everything that this tool does just fine elsewhere, but I think it's more convenient and time saving. Plus the highlighting is nice too. Makes it a bit easier to read.

[cl58]

Okay, so whenever there is an issue with the records, we (the admins) just have to synchronize the nameservers?

[Piotr GRD]

Or do whatever else will be required and possible to do to fix the problem. Sometimes there may be problem with just one domain - in such case manual update may take less time and resources than full synchronisation.

I am mainly trying to diagnose problems and - if possible - create tools that may help to diagnose these problems more easily, quickly, automatically. I can also suggest some solutions, like ie. in here, but every time the decision have to be made by a human admin regarding specific current situation. My tools are only automatic scripts that may not detect some specific situations which can be determined only by human after seeing the data provided by these or other various tools.



@ Krydos
Thank you. : )



By the way: another diagnostic utility, soon, link will appear on my other utilities.

[mailftp]

My tool will be useful in a case of some problems with HelioHost nameservers.

cody.heliohost.org resolves on ns2 but NXDOMAIN on ns1. Do I need to alert somebody else?

 

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