5000 internet loss

[Martin Liddle]

GrahamRHK – 2 hours ago  » 

I have seen this with my old (and early) Draytek 2760 which was built with LINUX firmware, now discontinued.

I would expect that most routers use Linux based software; do you believe otherwise?

The question now is why, with DNS set as router address, the router DNS cache loses the correct IP addresses of external web sites (there are very many) that are needed for correct FVP operation. Either the DNS cache gets corrupted or (and this occurred to me in the small hours) the external sites change their addresses and the DNS cache doesn’t get updated.

I think most routers are using dnsasq to achieve this. You might want to work through the changelog for dnsmasq and see if you can spot something; I bet a lot of routers are using old versions; see http://www.thekelleys.org.uk/dnsmasq/doc.html

The simple resolution would be to allow fixed IP addresses for FVP and DNS servers (non DHCP) – which one can do with a wired connection but not for a wireless connection. That is something for HUMAX to address possibly.

I have this nagging feeling that Barry posted a method to enable a fixed IP address to be set for a wireless connection but not sure if it was for an FVP or one of the other Humax boxes. Can anybody confirm my vague recollection?

[Anonymous]

Quote:

I would expect that most routers use Linux based software; do you believe otherwise?

Draytek routers use an operating system called DrayOS (proprietary). Of course that may well be based on one of the free UNIX based distributions – I don’t know. All I can say is that the early versions of Draytek 2760 had a rewritten OS based on LINUX; which was replaced in the product cycle with DrayOS. I believe all Draytek routers now use DrayOS.

Quote:

I think most routers are using dnsasq to achieve this.

I am sure you are right about this – I assume you meant dnsmasq. The changelog will take some time to study – and the releases don’t have dates associated; but I will work through it when time allows.

Quote:

I have this nagging feeling that Barry posted a method to enable a fixed IP address to be set for a wireless connection

That would be very useful if so. In the meantime, when I have time, I could try to force a test by using a wired connection and setting the DNS addresses to those of the router. To see whether the problem can be reproduced under controlled conditions.

Thanks for your interest in this problem. The technical details may be a bit complex – but it does seem that many FVP users experience difficulties with internet access and if we could work out what is happening we would have many happy bunnies.

[Martin Liddle]

GrahamRHK – 1 hour ago  » 

Draytek routers use an operating system called DrayOS (proprietary). Of course that may well be based on one of the free UNIX based distributions – I don’t know. All I can say is that the early versions of Draytek 2760 had a rewritten OS based on LINUX; which was replaced in the product cycle with DrayOS. I believe all Draytek routers now use DrayOS.

OK I didn’t realise that Draytek had switched to a non Linux OS; please forgive my ignorance.

Thanks for your interest in this problem.

My interest in the problem is because I have always used OpenDNS for DNS and suffer none of the problems reported by people using their router to supply DNS and wonder why. I have had problems with ISP DNS and with Google DNS (not related to PVRs) but over several years I have had no issues with OpenDNS (but I suspect other DNS services would also work well). I agree with you that the problem is likely to be somehow related to the networking interaction between the Humax and the router. I have seen people who know way more than me about networking say unpleasant things about dnsmasq. Is there a networking professional on the Forum?

[Anonymous]

Humax sent me a replacement unit which I have now set up. So far so good, all seems to be working. But after reading the posts by you good guys, I’m not holding my breath.

[Anonymous]

Quote:

Humax sent me a replacement unit which I have now set up

I am always surprised by how willing HUMAX seem to be to send a replacement box. If the box didn’t work at all or didn’t do some of the basics then that would be logical. But here we have a tricky networking problem – and quite why new hardware would fix a communication problem I don’t know. From your screen shots it seems that the problem is “upstream” from the FVP. I am still trying to replicate the problem here – without success to date. My hunch is that some routers don’t clear the dns cache as often as they should. What I can say is that many of the internet servers, to which the FVP has to connect, have different IP addresses as time goes by (over several days). So a dns call to the router may be returned an old IP address which may not work. If anyone is interested in this bit of research then send me a PM.

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