Network/browser issues

[qorje]

Hi, I've searched the forums, but didn't find my answer. I'm sure I'm not the only one who had this problem, so I'd be glad for any helpful link... However, many topics which seemed to solve a similar problem didn't help me at all.

Description:

1) Websites sometimes don't load in Firefox on Linux Mint and Sabayon Linux
-> It seems not to matter which site
-> Just checked on Mint, IPv6 is disabled in Firefox, don't know if that matters

2) Websites very often don't load in Google Chrome (everywhere) and Firefox (several Ubuntu installations)
-> Here it's heavily dependent on which site it is. for instance, Google's pages work well.

- I'm on a Windows 7 host now. On Windows XP and Windos Vista, I didn't have these problems
- I've tried several ways to stop this behavior... Disabling ipv6 in Firefox and Chrome, editing resolv.conf, etc.
- Everything works well on the host and on a different computer in the network (the Vista machine), so I don't think it's my network.

My guess is that it is something about ipv6, but disabling in Firefox doesn't solve it.
Another guess was DNS, but the same site is still affected more than once in a row. Reloading often helps.

[whit]

I've seen a few cases of trouble loading websites on an Ubuntu guest with a Win7 host. Haven't noticed any pattern to it. Most sites do fine while a few fail. Haven't checked whether the sites are generally available at the time as you have. My impression is it happens more when I'm at the edge of the wireless range, this being on a netbook.

The other possibility is it's something weird in what Windows is calling its firewall. Haven't tried turning that off.

[whit]

Saw this again getting to certain pages on some sites, that either nothing would happen to load the page, or it would take repeated requests to get it to finally load. Switched VB from NAT to bridge, and the problem went away. It may be that something gets lost in NATranslation, since the LAN goes through Netfilter/iptables SNAT to get to the net, so with VB NAT on traffic is getting NATed twice.

Is running in NAT mode behind a NAT something others have found problematic?

[whit]

I've found one location where this is 100% reproducible, that NAT doesn't work, but bridged does. This is with an Ubuntu 10.04 guest on a Win7 host, over wireless, with the Win firewall software turned off. Either way, NAT or bridged, I can go to dailykos.com. If I go to the Login page (being logged out) and try to log in, it will just pause forever, and not go through with the server connection, if I'm using the VB NAT. If I'm bridged, it goes right through. So this has nothing to do with Win's firewall. And it has nothing to do with DNS - since I'm already at dailykos.com, and have even installed a local bind9 on the client as the first to look up against.

It might have something to do with the LAN being NATed to the net through a Linux Netfilter firewall. Does this happen on earlier Win versions? Is there some known bug with VB's NAT?

[qorje]

It looks like the reason was my Netgear router. Reading their support page I read something about troubles with double NAT.

I upgraded the Netgear router to a new firmware version and set networking in VB to bridget mode and didn't have issues since.