DNS problems?

[greencreeper]

Incredibly slow browsing with loads of DNS errors. Changing proxy makes no difference. Ditto a modem reboot. Dunno what's up. :( It went tits up a few days ago - ping times, including to the UBR, of 3000+ on average. There's this on the server status page:

the morning of 12/05/2004 between 01:00 and 05:00 the following work will take place: Broadband customers in Leeds, Harrogate and York may lose their connection during this time due to dhcp upgrades. A reboot of the modem followed by PC will restore the conection.

But it's not "this time" and I haven't lost my connection - it just doesn't work :rolleyes:

[Paul K]

Since NTL is not exactly the most reliable when it comes to DNS I use a piece of software from
http://ntcanuck.com/
Have you contacted CS to see if there is a local issue?

[greencreeper]

I thought they changed their hours and only work until early evening?? I can't keep with the all the machinations - it's like the West Wing :D Me wonders if the engineers, bless 'em, want to finish early and have started faffing early :(

[Paul K]

Might need to contact CS in the morning but they may be able to tell you if your area experienced any problems this week.

[greencreeper]

Will do if things don't improve.

[rdhw]

Incredibly slow browsing with loads of DNS errors. Changing proxy makes no difference.Naturally, I don't know the details of your case, but in general it is fair to say that the majority of faults which present themselves to users as apparent DNS errors are not in fact DNS problems. The more likely suspects are:
- Web proxy servers (which affect only web-based traffic);
- Users' own firewall being over-picky.

You can test the web proxy possibility by configuring alternate web proxies. You can test the firewall possibility by configuring your firewall to allow all DNS traffic all of the time.ping times, including to the UBR, of 3000+ on average.That's another issue altogether, which might be producing false DNS-error symptoms. One possibility here is that your PC has got some malware or P2P file-sharing system which is saturating your cable modem upstream rate cap. Have a look around your PC for possible problems of this nature.

[greencreeper]

Incredibly slow browsing with loads of DNS errors. Changing proxy makes no difference.

Naturally, I don't know the details of your case, but in general it is fair to say that the majority of faults which present themselves to users as apparent DNS errors are not in fact DNS problems. The more likely suspects are:
- Web proxy servers (which affect only web-based traffic);
- Users' own firewall being over-picky.

You can test the web proxy possibility by configuring alternate web proxies. You can test the firewall possibility by configuring your firewall to allow all DNS traffic all of the time.

You're correct if the symptoms are in isolation - i.e. everything fine except for slow browsing and DNS errors. However, a tracert returned normal timings but took an absolute age to do so - because the DNS lookups were taking several seconds to return. I did try alternate proxies and it made no difference. My firewall is configured correctly - DNS traffic is allowed.

ping times, including to the UBR, of 3000+ on average.

That's another issue altogether, which might be producing false DNS-error symptoms. One possibility here is that your PC has got some malware or P2P file-sharing system which is saturating your cable modem upstream rate cap. Have a look around your PC for possible problems of this nature.

Dodgy software would have to get past the run-on-boot monitor and firewall - unlikely. The P2P software I use is configured to disallow uploads to avoid saturation. The only time I've had a virus on a PC was at work - which says it all really :D I don't visit dodgy websites ;) so malware is pretty unlikely. A modem reboot fixed the excessive ping times - I'm assuming that engineers changed something, causing the glitch. Might have just been one of those things though.

I haven't been online all day - just come on now and it's still naff. Cable modem diagnostics are fine so I can only assume that the recent engineering work is responsible. I guess I will have to brave tech support :( Never had connection problems (not major ones) until now :cry: