Guys, I'm desperate to get to the bottom of an issue affecting our sites on a VPS located in the US. Basically, we've noticed a sharp decline in the visitor number recently and on further investigation it turns out many people can't get to our sites/server. Now I had initially contacted our host (who I do trust 100%) and he looked into the issue for me. After a while he couldn't determine why some people were unable to connect as everything was A-OK at the server/datacenter end, so I tried a few alternative ISP's (friends and family internets, etc) and it appeared that those ISP's affected were AOL, Virgin Media and more recently PlusNet. Now, every tracert I did from those connections has shown the route stops at cogentco.com. I also had a response from someone in Bulgaria telling me they couldn't get to the site, and again their tracert shows the route stops at congentco.com. It appears the problem is with a London based route and I'm wondering if there is anything else I can do from the server end to test and verify these guys are definately the problem. I've already attempted to contact Congentco as well as AOL, Virgin Media and Plusnet but I'm not holding my breath as I can only presume they will already know of the issues probably because they are all in dispute with each other and that's why the issue exists!. Any advice anyone can offer is greatly appreciated. Many Thanks Mark
Hi Mark I think you have the right idea regarding the issue. Talk to your host, tell them if the routing issue isn't resolved you will find hosting else where as you cannot keep telling your clients that your site is down on there side due to routing issues between some bandwidth providers. Getting the message to the upstream provider of your host is your best option afaik. Other than that, there isn't much you can do other than - put your sites onto a different IP - request another IP from your host and trial the connections. I hope you get the issue resolved. Regards, Logan @ SSANZ
Hi SSANZ, I don't think changing our host would be an option because as far as I can see it isn't an issue with them, it's an issue with the route's certain ISP's choose to take to get to us, but I do agree 100% with you when we have to tell visitors about the issues as they are often not as understanding or appreciative as the rest of us when faced with such problems and troubleshooting the issue which often leads us down unexpected and unusual roads!. Like today, I sent many people an email from our Yahoo account asking if they could get to our site, and these were the people who were bouncing mail back to us at one point (hence the reason for sending is from our yahoo account) and while we received no NDR's back I received a few responses from people saying they haven't been able to get to the site now for 3-4 weeks. I replied to 2 of them, and I got a NDR back from one!??. The NDR came back from someone who had only just replied to me at my yahoo mail account and I replied to them from my yahoo mail account!. What the hell???!! So you see my problem, things aren't adding up! Even yahoo seem to be hit and miss - hopefully though from those who do get my mail and manage to respond I'll be able to see their tracert's and get some idea of where the problem lay Cheers Mark
It is an issue with your host. They (or their upstream) chose to use cogent as a bandwidth provider and now people can't connect to your site because of it. You may want to do some research on cogent. They are considered a low quality provider that keeps getting into battles with other bandwidth providers. You need to change to a hosting provider that does not use cogent.
Guys, I apologise if I'm missing something here and if I am please do try and explain it again, but here's how I see the issue. Cogentco is nothing to do with our host, and when I refer to our host I mean the people who are responsible for our server/sites in the US and not our host as in our ISP. My ISP is BE PRO and do not use cogentco to route their traffic and as such I have no issue's getting to my sites myself. As for our website host, they are not responsible for determining how the likes of AOL, Virgin Media or PlusNET customers get to our site and although their datacenter will obviously be using certain provider to have our servers on the net, from my investigations Cogentco are not in any way connected to those datacenters. Here, for example is a tracert directly from our server to my home IP address: We can see from this that cogentco are no-where to be seen and this is path from our server outwards. Other tracert's from our server show similar results. However the common denominator is when those who cannot see our site run a tracert and it always stops at cogentco.com and goes no further. This means the ISP that person is using is using cogentco as their preferred peer and it appears to be an issue with cogentco in every way. I'm certainly no expert on the whole internet route thing, but from my limited knowledge it's clear cogentco are to blame and it is those ISP's who choose to use them that are affected. So far, we've found someone from Poland and Bulgaria affected and their tracert's stop at cogentco.com in London which also then tells me the US will probably not be affected but Europe routing through cogentco will. Hope that all makes sense! Mark
level3 and cogent aren't exactly the best of friends: http://www.google.com.pk/search?q=l...g.mozilla:en-US:official&hs=NJt&start=10&sa=N Mind you that was 4 years ago.
abdussamad, I've seen a few similar reports on the net also but none that recent although strangely enough I was also using host-tracker off and on over the past few weeks and I noticed that they were reporting our sites as non reachable from parts of Hong Kong, Germany and Russia though just today all locations are now reporting success in reaching the sites so I don't know if it's related and now fixed or whether it's pure coincidence! Guess I'll find out when other members have managed to contact me Cheers Mark
Hi, You should provide your hosting provider with a traceroute from both directions. (i.e. Server A -> Server B, Server B -> Server A) They should resolve the problem or you should switch providers.
Guys, I don't really know how else to explain this other than what I've already tried but I can't emphasise enough that this isn't something our host has control over or is at fault over. I am now 100% sure after much prodding and poking that cogentco were/are to blame - let me try and put this another way for those who are still unsure ... I'm with BE Pro for my internet, my friend is with AOL. Both ISP's will talk to each other through their routes and a peering agreement will have been reached. Let's now say AOL fall out with BE Pro, what happens then is any location throughout the world that AOL are used to get to will be inaccessible to BE Pro users (i.e. me) and any location that BE Pro must be used to get to will be inaccessible to AOL users (my friend) whereas other ISP's won't be affected. ISP's can't simply serve everything, they must co-operate with other ISP's and this is where peering agreements happen, but if one falls out with the other then it means their users can't get to certain locations if they depend on the peering partner they have just fell out with!. Cogentco are one such peering partner of AOL, Virgin Media and PlusNet and although I now know there wasn't any fall out between them all, it is apparent cogentco had issues from London and this is why traffic was affected for those customers of AOL, VM and PlusNet. All said and done, it looks as though cogentco are now re-routing traffic previously destined for the London router and traffic is flowing good once again, but I'm really surprised on how long it has taken them to do this given the amount of people I guess that were affected!. Mark
it is not an issue with his host directly... You need to read what hes saying, properly. The issue is with a peer route - telling his host isn't going to do much, the host is just going to talk to there upstream provider and say - hey, cogent doesn't like the peer route, can we do something about it. The upstream provider will say no, they dont want to piss on the neighbours fence do they? Cogent is in fact, not a low quality network - its quality of service is high for its price, however - Its reliability is not 99%. Also, another correction - he doesn't need to move hosts, he just needs to move IP's. Why is it that i correct peoples silly replies a large majority of the time?
The truth of the matter is any website could be affected by any one of the links in the long chain of dependancies on it's journey from the browser to the server and it's often not the fault of the server but an issue between the client trying to get to through it's ISP or the ISP trying to get to the server. In my case changing anything at our server end wouldn't have made a difference in this particular matter because our physical location would have remained the same therefore those experiencing issues in getting to us would have faced the same problem as their ISP's would still be using cogentco to get to us. It's also very true that cogentco are about as reliable as a wet paper bag and I can't believe they are still in business to be honest, but as I say it looks like whatever issues they were experiencing they have now been resolved and those who were previously unable to get to our sites/server are now able to, happy days! Marl