Error 404 Vhost unknown

[joddle]

I belong to a society which has a professionally hosted website which can be accessed by members to get newsletters and other information.

Recently we did a circular to our members and they needed to look at the website to get some things but for a few of them they could not connect to the site and all had the same message "Error 404 Vhost unknown". In all cases they can go to other websites without any issues. Most other people had no issues at all.

 

So far:

We have contacted the hosting company and so far they can see no reason for this

We contacted the affected people to see if there was anything common about their systems but not apparent commonality

We asked them to access our site via a provided link, via google and from typing URLs into their browsers but they always get the same error message

 

So far we have learned little

 

1) the error occurs for any device for any particular person - i.e. they get the error if they use a pc, an I-pad, a mobile etc

2) the issue may not happen at one location (eg from home) but for the same person at another location the error occurs

3) the people use a variety of ISPs including Sky, BT.

 

It's all starting to be a bit of a mystery but one which we could do without - any ideas please!!!!!

[joddle]

Small update - one of those affected now finds he can access the site again but has no idea why or what has changed but another is still having the same issue

 

On searching the web we found that sometimes Enhanced Protection Morse can reveal the error but when I put one of my machines into this mode I could still access the site so nothing gained there. Still searching for a reason - so again appealing for any guidance!!!

[KenB]

Hi Joddle

 

If the error occurs for any device then obviously it looks like a website/server problem.

 

I am thinking that the individual accounts may be corrupt.

Try asking one of the members to re-register with a different name and email address.

 

[ Create a Gmail or similar address to test ]

[joddle]

Hi Joddle

 

If the error occurs for any device then obviously it looks like a website/server problem.

 

I am thinking that the individual accounts may be corrupt.

Try asking one of the members to re-register with a different name and email address.

 

[ Create a Gmail or similar address to test ]

 

That's what I was hoping but they can't even access the site - let alone log in.

 

It seems very odd because only 3 people have had this problems but all reported the same error message. They also get it on all their devices and although they can get to other websites they can't get to ours! The other hundreds of our member have no such problems!

[KenB]

Hi Joddle,

 

they can't even access the site - let alone log in.

If no device can access the site I wounder if this is IP Address related.

 

Ask your colleagues to firstly find their IP Address.

Simply Google "what is my ip address" - it will come up on screen.

Make a note of this.

 

The easiest way to change the IP Address is to turn their router off for half an hour.

Then switch back on.

Check to see if IP Address has changed.

 

If not - switch router off over night.

Try again in the morning.

Check that the IP Address is different. [ probably only the last 2 numbers will change ]

 

Most IP Addresses are dynamic - in other words if you are not using it the ISP will re-allocate your old one.

When you connect again you get allocated a new one.

 

Let me know how this goes.

[joddle]

Well things have not changed - our hosting company has changed the server thinking that might be causing he issue but its still the same

 

Only 4 out of 350 odd people are affected and they are using a variety of devices and browsers but all only get the error when trying to connect to our site.

We had hoped changing server might resolve things but the issue is the same for just the same 4 people.

 

One person has tried cleaning his registry and used antimalware and antivirus apps to ensure the machine is clean - but to no avail.

I still have to check if he turned off the router to gain a new IP address - will report when I know more

 

Still appealing for any suggestions

 

 

 

[KenB]

I still have to check if he turned off the router to gain a new IP address

This needs to be tried - however if,as you say, the people with the problem have tried from different locations then this is very odd.

 

You say that they cannot get to the site at all.

 

Can you post a link to the site please ?

Or PM me with it if you don't want it public.

[joddle]

This needs to be tried - however if,as you say, the people with the problem have tried from different locations then this is very odd.

 

You say that they cannot get to the site at all.

 

Can you post a link to the site please ?

Or PM me with it if you don't want it public.

 

The site is http://www.osobs.com - it won't be very interesting to most people.

 

One of the affected people is taking his ipad to a friend's house this weekend and will try connecting from there- he will also try and connect from his friends pc.

 

if he cant connect from his frinds PC then we wont know much more!!!

 

If he can connect from his friends pc then he will try also from his ipad.

If he can connect with his ipad as well then this points to a problem in his router or with his ISP

However if the ipad does not connect then there must be something in his own pc settings both on the Ipad and at home.

 

He has yet to report on rebooting therouter

[KenB]

I can access the site - but this was to be expected.

 

Ask one of the people who cannot access the site to do the following please:

Go to an elevated command prompt

In Win 10 Click the O in the bottom left corner of the screen [ Search ]

Type in .....cmd...... then in the left box right click on "Command prompt" and then click on "Run as Administrator"

At the prompt type ...

ping www.osobs.com .....hit ENTER [ there s a space after ping ]

 

Then try - at the command prompt - tracert www.osbos.com [ space after tracert ]

 

You should get something like this:

 

 

 

Microsoft Windows [Version 10.0.14393]

© 2016 Microsoft Corporation. All rights reserved.

 

 

C:\WINDOWS\system32>ping www.osobs.com

 

 

Pinging osobs.com [64.90.50.35] with 32 bytes of data:

Reply from 64.90.50.35: bytes=32 time=147ms TTL=48

Reply from 64.90.50.35: bytes=32 time=145ms TTL=48

Reply from 64.90.50.35: bytes=32 time=146ms TTL=48

Reply from 64.90.50.35: bytes=32 time=145ms TTL=48

 

 

Ping statistics for 64.90.50.35:

Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),

Approximate round trip times in milli-seconds:

Minimum = 145ms, Maximum = 147ms, Average = 145ms

 

 

C:\WINDOWS\system32>tracert www.osobs.com

 

 

Tracing route to osobs.com [64.90.50.35]

over a maximum of 30 hops:

 

 

1 <1 ms <1 ms <1 ms 192.168.1.1

2 11 ms 9 ms 8 ms host-92-13-192-1.as43234.net [92.13.192.1]

3 10 ms 14 ms 10 ms host-78-151-225-117.static.as13285.net [78.151.225.117]

4 10 ms 9 ms 10 ms host-78-151-225-112.static.as13285.net [78.151.225.112]

5 15 ms 15 ms 16 ms host-78-144-9-31.as13285.net [78.144.9.31]

6 17 ms 21 ms 23 ms v209.core1.lon1.he.net [216.66.84.213]

7 25 ms 21 ms 23 ms 10ge2-9.core1.lon2.he.net [72.52.92.222]

8 90 ms 83 ms 89 ms 100ge1-1.core1.nyc4.he.net [72.52.92.166]

9 105 ms 97 ms 97 ms 100ge14-1.core1.tor1.he.net [184.105.80.10]

10 123 ms 123 ms 127 ms 100ge6-1.core1.ywg1.he.net [184.105.64.102]

11 131 ms 134 ms 130 ms 100ge10-1.core1.yyc1.he.net [184.105.222.98]

12 148 ms 148 ms 189 ms 100ge10-2.core1.yvr1.he.net [184.105.64.113]

13 149 ms 148 ms 148 ms 100ge4-2.core1.sea1.he.net [184.105.64.109]

14 147 ms 146 ms 158 ms 100ge14-1.core1.pdx1.he.net [184.105.64.138]

15 148 ms 149 ms 146 ms dreamhost.10gigabitethernet10-5.core1.pdx1.he.net [65.49.80.226]

16 145 ms 148 ms 146 ms pdx1-cr-2.sd.dreamhost.com [66.33.200.3]

17 146 ms 148 ms 146 ms pdx1-a4u27-acc.sd.dreamhost.com [66.33.200.12]

18 145 ms 147 ms 145 ms apache2-rank.lafayette.dreamhost.com [64.90.50.35]

 

 

Trace complete.

 

 

C:\WINDOWS\system32>

 

If possible I would like to see the actual results.

To do this:

Top left of the Command Prompt Screen is a small, square black icon

Left click on this > Edit > Select All

CRTL + C .....this will copy the results

CTRL + V .....will paste them into Notepad / Word etc.

 

He could send this to you for you to post here. :)

 

Which Operating System is your friend using ?

[joddle]

I can access the site - but this was to be expected.

 

Ask one of the people who cannot access the site to do the following please:

Go to an elevated command prompt

In Win 10 Click the O in the bottom left corner of the screen [ Search ]

Type in .....cmd...... then in the left box right click on "Command prompt" and then click on "Run as Administrator"

At the prompt type ...

ping www.osobs.com .....hit ENTER [ there s a space after ping ]

 

Then try - at the command prompt - tracert www.osbos.com [ space after tracert ]

 

You should get something like this:

 

 

 

 

 

If possible I would like to see the actual results.

To do this:

Top left of the Command Prompt Screen is a small, square black icon

Left click on this > Edit > Select All

CRTL + C .....this will copy the results

CTRL + V .....will paste them into Notepad / Word etc.

 

He could send this to you for you to post here. :)

 

Many thanks for this - I will be in contact with him again soon and hope to get him to try it --

He is not so PC adept so he may not feel able to do that - but we will see.

[joddle]

Some time has passed but now one of my people is able to get onto our site again - his ISP (Sky) advised him to do the following

 

In Firefox or IE type in the web address bar 192.168.0.1 and the search takes you to Sky hub login. Username is admin and password is sky. Click - advanced - LANIP set up - cancel tick on enable IPV6 on LAN side - apply.

 

He said the router rebooted and then all was well. So is there a logical reason why that should be?

[joddle]

After another week or so I have been told by virtually everyone who has had this problem that it has been cured by changing the router settings for IPV6 in the way described in my earlier post.

 

So my questions now are :

 

a) Why is this seemingly only an issue our own site? We don't know of any other sites where the same people cannot browse normally.

 

b) Is it a programming issue - or something far more subtle? Any insight on this gratefully appreciated.

[KenB]

Hi,

 

If all members who had the problem are Sky users it looks like a problem [ setting ] at their end relating to IPv6 and your particular site.

[joddle]

Hi,

 

If all members who had the problem are Sky users it looks like a problem [ setting ] at their end relating to IPv6 and your particular site.

 

Alas not so straightforward

 

One Sky, one Clara Net, One BT and one currently unknown!

 

The three known ones all tweaked the IPV6 settings and then could access our site - so it appears the issue may be with the way the site handles traffic from their routers with that setting - is that possible?

[KenB]

One Sky, one Clara Net, One BT

This is indeed an odd one.

 

IPv6 is the way forward and IPv4 will be phased out in time.

 

It could be that the hosts for the website don't support IPv6 [ which would be odd ]

It may be worth contacting them and asking.

 

I will see if I can find anything more.

 

EDIT:

It looks like the host is BB-Online.net

[joddle]

This is indeed an odd one.

IPv6 is the way forward and IPv4 will be phased out in time.

It could be that the hosts for the website don't support IPv6 [ which would be odd ]

It may be worth contacting them and asking.

I will see if I can find anything more.

EDIT: It looks like the host is BB-Online.net

 

 

I approached the guy who designed and maintains our website and he said the following - does this seem logical to you?

 

"I think it's down to cached IPv6 records on these routers.

 

At some point in the past, there was an extra record which no longer exists and it's been cached.

 

So, because the routers aren't behaving correctly, they're keeping hold of an expired domain name record and as IPv6 records take precedence over anything else, these users were being sent to the wrong place."

[KenB]

It makes some sense - I must admit I am not totally ok with web design and servers.

 

As I understand it:

 

The first time you access the webpage your router sends a request to your ISP Servers which basically says " what is the IP address of osobs.com? "

When the reply comes back your router remembers this and passes this back to your computer.

The next time you attempt to access the website there is no need to access your ISP Servers because all the relevant information is stored locally on your system.

 

If I understand what your web controller has said .....

 

The original / extra Domain Name Record for your osobs.com site was deleted from the servers.[ cached ]

So when your IPv6 setting tried to access the website servers looking for the original osobs.com it simply wasn't there.

 

Removing the IPv6 setting in the Router meant that when you then tried to access the website again it was as if it was a new request.

The router was then directed to the working website on the Servers.

 

This is probably over-simplified but it does seem to explain why some of your members couldn't access the site.

 

Just a further note:

Not all routers act in this manner - which will explain why so few of your members had the problem.

 

I hope this helps.

[joddle]

It makes some sense - I must admit I am not totally ok with web design and servers.

 

As I understand it:

 

The first time you access the webpage your router sends a request to your ISP Servers which basically says " what is the IP address of osobs.com? "

When the reply comes back your router remembers this and passes this back to your computer.

The next time you attempt to access the website there is no need to access your ISP Servers because all the relevant information is stored locally on your system.

 

If I understand what your web controller has said .....

 

The original / extra Domain Name Record for your osobs.com site was deleted from the servers.[ cached ]

So when your IPv6 setting tried to access the website servers looking for the original osobs.com it simply wasn't there.

 

Removing the IPv6 setting in the Router meant that when you then tried to access the website again it was as if it was a new request.

The router was then directed to the working website on the Servers.

 

This is probably over-simplified but it does seem to explain why some of your members couldn't access the site.

 

Just a further note:

Not all routers act in this manner - which will explain why so few of your members had the problem.

 

I hope this helps.

 

All makes perfect sense - many thanks.