Same site, 2 addresses - one doesn't work

I have 2 BQMs which refer to the same site - my home server.
One is addressed via DDNS.net - it works fine.

The other uses a 'home.' subdomain on my hosted website. The subdomain is pointed to my home IP address. Entering the subdomain web address in a browser works fine.
But the BQM does not display - the panel is greyed-out with "NO DATA" in front.

I can's see any info about what might cause this.
Any help appreciated.

Thanks, AB

I think this is basically the same question about using BQM on a subdomain: https://forums.thinkbroadband.com/bqm/f/4779750-bqm-...

As I understand it the Ping request from the BQM would be sent to your router's external IP address and the router will respond to the Ping... in some routers it may be possible to direct the Ping through to an internal server. But Ping operates at the IP address level, Layer3.
Generally in the consumer set up the Ping goes to the router which responds without passing it through to any internal servers, you should ask the ThinkBroadband team specifically how BQM tries to resolve a subdomain... but you send a Ping to an IP address so unless your subdomain has it's own different external IP address you won't be able to reach it with a Ping request from an external server.

Thanks for this.
I don't see how the fact it's a subdomain should affect this;
- the DDNS.net address resolves to my home IP - and the BQM for that address works OK
- the web address for my subdomain also resolves to my home IP address but that BQM does not work.

Clearly there IS a difference, but I can pingboth addreses, and both resolve to the same IP....

Thanks,
AB

In reply to a post by ACC_B:

Clearly there IS a difference, but I can pingboth addreses, and both resolve to the same IP....

Most likely when the BQM queries your DDNS.net service it does not respond, perhaps it thinks the BQM is abusing the service? I found the ASUS router built in DDNS service stopped working with BQM years ago, and now I use a third party instead.

I assume your web address for your subdomain (e.g. myhome.myname.uk) is using a different type of Dynamic DNS or you are lucky to have a fixed IP broadband.

You've found an incompatibility on the internet, and have a workaround, don't sweat it.

Thanks for the reply.

It's the DDNS.net address that works.
The subdomain DNS is handled by my web host, and the home.* subdomain
- pings successfully (resolves to my home IP),
- displays the correct page on a browser,
but gives 'NO DATA' on the BQM panel.

AB

It is probably worth asking the thinkbroadband team if there is an issue with how BQM is trying to resolve subdomains. You can send them an email here: [email protected]

As I noted earlier there was a recent thread on the same topic, so there might be some anomaly on how BQM resolves the URL to an IP....
But as discussed it will resolve to the same IP address and get responded to by the router, so it could be a waste of effort sorting out the subdomain.

I'll take your advice and pursue it.

But I don't think I've made it clear - the router is responding to the BQM request correctly - for either the IP address itself, or for the ddns.net dynamic address. It's only when I give BQM the 'home' subdomain, that it fails. So I don't think it's to do with how the router is responding.

Agreed... it looks like it is how BQM is trying to resolve the URL. However I was trying to say that when it works the router will be responding to subdomain as well as your ddns address (unless you have a different external IP address for the subdomain) so I can't see the benefit of being able to use BQM to graph the subdomain as well. In fact reading the BQM FAQ I suspect that BQM would recognize that the subdomain (if it worked) is resolving to an IP address for which there is already a BQM set up (on the ddns.net address) and would reject it anyway.

But I am guessing a bit and it would be best to contact the "team" to get their response.

In reply to a post by Bam16:

... In fact reading the BQM FAQ I suspect that BQM would recognize that the subdomain (if it worked) is resolving to an IP address for which there is already a BQM set up (on the ddns.net address) and would reject it anyway.

But I am guessing a bit and it would be best to contact the "team" to get their response.

Not necessary to contact the team for this. Your hypothesis can be tested by removing the BQM for the router or the main domain

In reply to a post by ACC_B:

The subdomain DNS is handled by my web host, and the home.* subdomain
- pings successfully (resolves to my home IP),
- displays the correct page on a browser,
but gives 'NO DATA' on the BQM panel.

As you don't give specifics, lets make some assumptions. I assume you are using shared hosting, and you have delegated the domain name (lets use madeup.co.uk) to the shared hosting provider who give you a DNS control panel. You have configured a host of "home.madeup.co.uk" to point to your broadband IP, and asking the BQM to ping the home.madeup.co.uk domain. I also assume you have a home broadband with a frequently changing IP so you can't simple set up an A record for this, but are using a service of the shared hosting company to act as a dynamic DNS provider.

It is quite possible the ThinkBroadband BQM "pingbox" (the firebrick) is doing a DNS query for your IP more often than the shared hosting provider thinks is reasonable, and so they chose not to reply.

The fact it works with other DNS providers means this can't be an issue with the BQM, it is a choice the DNS service provider has made to not respond. They may assume the BQM is something malicious due to high volume.

In reply to a post by Bam16:

Agreed... it looks like it is how BQM is trying to resolve the URL.

A hostname is not a URL; you need a fully qualified hostname within a URL.

The BQM uses an AAISP Firebrick, and it is not that long ago that DNS support was added. Previously you had to give the system an IP address and remember to change the BQM if your IP changed, or you pinged someone else.

This sounds like a possibility.
Thanks. AB

I did see your e-mail over the weekend and got the developer looking into this as we've had a handful of cases where some BQMs don't work. It's nothing obvious but the Firebrick isn't working properly with them but trying to find out why

seb

Thanks for looking at it.
I've tried a couple of things, and have (only now!) just realised that my hosted domain (tld or any subdomain) shows the same 'NO DATA' result.
So I'm now looking to see if there are any parameters I can change there.
AB

In reply to a post by ACC_B:

Thanks for looking at it.
I've tried a couple of things, and have (only now!) just realised that my hosted domain (tld or any subdomain) shows the same 'NO DATA' result.
So I'm now looking to see if there are any parameters I can change there.
AB

There's something weird going on with the firebrick.. I'm not sure right now if it's related to DNS resolution or not but I see no reason it shouldn't work.

if both urls are resolving to the same IP wouldnt the BQM only send the received ping data to the first monitor it finds with that IP. ?? and thus would by marking all data to the working bqm while showing no data on the duplicate ip bqm

Edited by pyarwood (Sun 02-Nov-25 17:47:57)

In reply to a post by pyarwood:

if both urls are resolving to the same IP wouldnt the BQM only send the received ping data to the first monitor it finds with that IP. ?? and thus would by marking all data to the working bqm while showing no data on the duplicate ip bqm

I saw this first time around and it didn't register with me But I think that the answer is this:

Probably BQM works primarily with host IPs. It will only work with URL's which resolve to an IP address. The problem here will be that when OP sets up a BQM for <hostname>/<IP redirect>, this will resolve to the IP for <hostname> and BQM need look no further for an IP address. Hence the BQM will only look at the IP address used by the hosting provider. BQM will not look beyond <hostname> and cannot interpret <hostname>/<IP redirect> as a different address because <hostname>/<IP redirect> has no meaning in IP address resolution syntax.

Or put another way, <hostname>/<IP redirect> is a URL only for HTTP[s] syntax whereas IP address resolution syntax works exclusively with hostnames and not with URLs.

In reply to a post by pyarwood:

if both urls are resolving to the same IP wouldnt the BQM only send the received ping data to the first monitor it finds with that IP. ?? and thus would by marking all data to the working bqm while showing no data on the duplicate ip bqm

We send the hostname to the Firebrick (the device which does the pings) which does the resolution. If two entries exist with the same hostname we will send both through (as we do with IPs). I'm not sure how it may or may not cache the resolved hostname. We separately track the hostname-to-ip mappings in another system for troubleshooting (including to deal with the "you're pinging me and I didn't ask you to" e-mails we get from time to time as they may be outdates BQMs on a hostname not IP.

Unless there's a firebrick bug there shouldn't be an issue with multiple monitors (although we do limit it to 3 in total per host/IP; that happens before the firebrick).

The 'no data' issue is weird.. we have situations where refreshing the page produces data.. We're just working on another thing but need to look into this.

seb