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[Sunny]

It's off and on at work network but mobile works fine.

 

[kuoh]

It seems to be better for me this past week, but I'm not sure if it's because I'm just visiting less. At home I check the site between a phone, tablet, 2 laptops and 2 desktops depending on where I am in the house, so if it's blocking strictly on sessions per IP, then I can see why there could be trouble.

KuoH

Just had the issue here when I opened a load of tabs in Chrome - I guess he firewall flags it for too many connections as a potential DoS maybe.

 

[Dashmellow]

I was one of the first people to report this problem going back to around May 7th and worked with DCM trying to pin down the problem and try to resolve it. That was around the same time I figured out that I could connect to DCT via proxy but that my usual IP address would get blocked in 90 seconds or less after logging in or even just visiting. So, I was very happy after almost two weeks of this that the problem seemed resolved but at least for me it now seems to have started all over again this morning. If I reboot my DSL modem and generate a new dynamic IP address I can again access DCT but if this starts to play out like last time, DCT's host will eventually start blocking the whole range of IP addresses coming from my ISP.

Is anyone else starting to have this problem again?

 

[DT MI]

...Is anyone else starting to have this problem again?

I too was having problems earlier (over the last couple weeks). Been off and on most of the morning today and everything has been fine. (So far, keeping fingers crossed.)

Edit: I should have said I've been off and on the site so as not to be confused with access to the site being off and on. Access has been unencumbered <--- I really like that word.

 

[Dashmellow]

I too was having problems earlier (over the last couple weeks). Been off and on most of the morning today and everything has been fine. (So far, keeping fingers crossed.)

Let's hope so!

 

[DT MI]

Elaborating a bit on my last post. I use Firefox as my browser and have most security settings set pretty high. A couple of times over the past few days I've received the attached warning message. This is likely related to the recent attempts to 'highjack' the site and what the DCT host service is/was trying to stop.

 

[Dashmellow]

I too use Firefox as my main browser and get that warning on occasion. I use a variety of security and privacy add-ons, plug-ins and extensions and occasionally the settings on some of these can cause "false positives" that turn out to be nothing. Nevertheless, I always pay attention to them anyway. Often that warning you posted is indeed valid and that may be the case here. I also use NoScript and this requires experience and knowledge regarding which scripts to allow or deny for proper page functionality. During my attempts to understand what is going on here with not being able to access DCT there has been evidence of multiple simultaneous connection attempts allegedly coming from my computer (according to DCT's hosting service) that I have been unable to identify or confirm. I use a reverse firewall that would alert me via a graphic interface to any outgoing connection attempt or ping in real time and I'm not seeing anything like that. In my conversations with DCM I have speculated that there may be some sort of D0S or SSL attack happening here and I am still inclined to think that is a possibility. At one point recently Firefox generated the follow warning:

 

[DT MI]

^^^ Interesting, I've never seen that warning - ever. Running dual firewalls myself (H/W and S/W) so there's some things I'll never see unless I go looking for them, like ping attempts that are stopped on the H/W level.

 

[Dashmellow]

I had never seen that warning before either!

I have wondered whether it has anything to do with the FREAK Attack vulnerability that was made public less than three months ago and that a few IT people I've talked to haven't heard of!

This problem has been widely patched by now but not everywhere.

https://freakattack.com/

https://en.wikipedia.org/wiki/FREAK_attack

 

[DT MI]

Interesting - and I'd not heard of that either. Going to have to study it a bit to learn more about it. Ironic in that umich.edu is one of the vulnerable sites. Really glad that Firefox is the default browser on all my machines since it seems that every site my wife uses is on that list.

 

[Dashmellow]

It's weird but every time I mention FREAK attack to someone who I would expect to be otherwise knowledgeable and aware of such things, including some IT professionals they express shock and surprise when they discover that it is real and quite serious.

 

[DT MI]

The problem is, and always has been, there are so many different sectors in the industry it's impossible to keep track of everything that's happening. Just trying to read all the trade journals would be a full-time job - plus. I've been out of the industry for about 9 years now and it would be like starting out at day one if I tried to reenter - even given that I probably spend 10 hours a week trying to stay in touch because I still find it interesting.

 

[Dashmellow]

I hear you! Been there myself.

 

[DashCamMan]

Seems like the most common reason for being blocked is too many connections. In Firefox you can check this by going to:
about:config
search for:
network.http.max-persistent-connections-per-server
If this number is high and you open multiple tabs / browsers you may be temporarily banned due to too many connections.

 

[DT MI]

Seems like the most common reason for being blocked is too many connections. In Firefox you can check this by going to:
about:config
search for:
network.http.max-persistent-connections-per-server
If this number is high and you open multiple tabs / browsers you may be temporarily banned due to too many connections.

Is 6 considered high? This is what mine is set at and I've been one of those who've been locked out over that last couple of weeks.

 

[Sunny]

I never had issues at home neither with Firefox nor with chrome but we only have Internet Explorer at work and that is where it started acting up since few weeks.

 

[Dashmellow]

Seems like the most common reason for being blocked is too many connections. In Firefox you can check this by going to:
about:config
search for:
network.http.max-persistent-connections-per-server
If this number is high and you open multiple tabs / browsers you may be temporarily banned due to too many connections.

Mine is set to 6 as well which is apparently the Firefox default. During our PM discussions about this issue you reported to me that your hosting provider stated that my IP address was being blocked because more than 20 connections were open simultaneously and they said they "increased the connection limit from 20 to 50 to avoid this issue", (for my IP range) so it would appear that something else must going on here. I'm not usually in the habit of opening a great many tabs at once anyway.

I know I've said this before several times but I will repeat it again: If I reboot my DSL modem to generate a fresh IP address, restart Firefox (or any other standard browser) so that it's cache, cookies, history etc, are flushed and then go to the DCT forum I sometimes get blocked again within sixty to 90 seconds without opening any tabs at all or in some cases not even clicking on anything. How can Firefox open too many connections just by visiting a page for that amount of time and not doing anything? Also, as I mentioned earlier, the ancillary extensions I run with Firefox will block scripts and embedded links from opening any connections without my first granting permissions.

Anyway, I'm happy to report that the connectivity problems I experienced this morning seem to be back to normal.

 

[DT MI]

...repeat it again: If I reboot my DSL modem to generate a fresh IP address, restart Firefox (or any other standard browser) so that it's cache, cookies, history etc, are flushed and then go to the DCT forum I sometimes get blocked again within sixty to 90 seconds without opening any tabs at all or in some cases not even clicking on anything.....

That was essentially my experience as well. I would shut down my entire system, reboot the cable modem (getting a new IP address), restart the router (on one occasion I even physically replaced the router) and would not be able to connect even once, much less for a period as long as 60 seconds.

 

[reverend]

It's not browser prefetching playing up is it maybe?

When I've had too much caffeine I've set off loads of firewalls when I'm click happy - even Google frequently asks if I'm a robot

I'm away at the min but will try some network traces when I go back home as well.

Are the raw access logs available from the hosting provider?

Sometimes transparent proxies at the ISP end can cause this sort of thing too with read ahead, it could be one of the many monitoring boxes that don't exist

Likewise one of the biggest UK ISPs has started dabbling with carrier grade NAT which is only going to start causing problems for some firewalls and apps down the road which aren't expecting it.

That reminds me I need to set up IPv6 at home soon too - I thought my now it would have been more widespread :/

 

[DT MI]

Elaborating a bit on my last post. I use Firefox as my browser and have most security settings set pretty high. A couple of times over the past few days I've received the attached warning message. This is likely related to the recent attempts to 'highjack' the site and what the DCT host service is/was trying to stop.

View attachment 13580

Just had this happen again and it lasted for about 5 minutes. It quit as fast as it started (although I did restart Firefox) and all is good again. Very strange...