External Network Availability

martin28uk · 07-05-2008, 19:57

Hi , Just joined the forums today in the hope of finding an answer to my dilemma.

I have a home network consisting of 3 PCS 1 XP machine 1 Vista , and an XBOX360, They are all connected to a Linksys WRT54GS + Virgin 4mb cable modem. I also have a linux SSH server running on the nework.

On my internal network everything is fine can connect to the internet ok and can ping resolve all IPS / Names from the command line.

However i could but cannot now connect to my router or linux server externaly I.E from work or friends houses etc. I use a DNS name from dyndns.org.

The Problem is i cannot ping / connect to this DNS name from an external host, the ping will resolve my cable modems external IP address but will allways time out The same commands on my internal network work fine and as expected. Also if i ping the cable modems IP address instead of the DNS name i experiance the same symtoms.

I have disabled all security aspects on my router Firewall etc to no avail.
This all was working last week and i could connect from an external host just fine both to my router and also to my ssh server via the port forwarding i set up.

Any ideas / help welcome thanks

AbyssUnderground · 07-05-2008, 21:53

The IP is dynamic so check the IP hasn't changed and no longer matches the IP on the dns name.

martin28uk · 08-05-2008, 06:37

thanks for the reply but i have checked the IP and it matches what is set as the DNS name, IP resolves from pinging the DNS name but times out after that.

Additionally the router has an automatic DNS update facility built in.

Am i in the right sort of area for this kind of problem? , looked the best fit at 1st glance.

I was wondering if it may be some form of blocking at VM end ?

Jon T · 08-05-2008, 08:16

Go to http://whatismyip.com on one of the PC's on your internal network, and check it's the same one as is resolving to your DDNS name.

Just because the ping is coming back ok and the name is resolving back just means that the IP address DynDNS has stored is live, it doesn't tell you whether or not it's still your ip address.

Edit: Read your posts again and it seems that you may have done some of this already. BTW, I have a similar setup to you, VPN, SSH, RDP and a few other bits still work.

whydoIneedatech · 08-05-2008, 10:48

Try putting the following inhto your address bar, at the bottom under the heading "Your Access Info" it will tell you your IP address and what UBR you are actually on, this is an Official Virginmedia Internet Tools page.

http://tools.virginmedia.com/

martin28uk · 08-05-2008, 18:29

thanks for your replies Jon T & whydoIneedatech just got back from work and only just seen the forums.

The results from whatismyip.com & the virgin media tools page both confirm my IP to be what the DNS name resolves as. 80.6.202.**

I thought allthough a bit stange my router had gotten itself corrupt so i have replaced it with another i had kicking about an edimax one.

This has very limited options on it and all security is off by default.
However the same problem exists upon adding this to the network and removing the linksys router, I cannot ping IP address externally from the network well i can ping just timeouts.
Internally all is ok. DNS name resolves my IP address as before.

Jon T · 08-05-2008, 18:54

Quote:

Originally Posted by martin28uk

thanks for your replies Jon T & whydoIneedatech just got back from work and only just seen the forums.

The results from whatismyip.com & the virgin media tools page both confirm my IP to be what the DNS name resolves as. 80.6.202.**

I thought allthough a bit stange my router had gotten itself corrupt so i have replaced it with another i had kicking about an edimax one.

This has very limited options on it and all security is off by default.
However the same problem exists upon adding this to the network and removing the linksys router, I cannot ping IP address externally from the network well i can ping just timeouts.
Internally all is ok. DNS name resolves my IP address as before.

Sorry for maybe reading this wrong, but your saying although you can browse a website from your PC that you cannot ping the same website. Try bbc.co.uk, should resolve to 212.58.224.131.

I know you've tried two routers, but there's no way on earth that Virgin block pings. Can you connect one of you PC's direct to the cable modem and check again?. PC must be set DHCP, and you must power cycle your cable modem each time you swap what's connected to it.

One other thought, are you running software firewalls on your PC's that somehow have had their settings changed.

martin28uk · 08-05-2008, 19:06

Jon T, all the PCs on the internal network (ie at home) can connect to the internet & can ping websites etc perfectly...

The only problem i have is i want to connect to my Home network from a remote place such as work or friends houses. This i cannot do at present
all connection requests time out and my Vigin Media IP cannot be pinged from outside my network (ie from a friends house or work) .

Here is an extract from my ping yesterday to my DNS name which shows what i mean about the IP address resolving from the DNS name but timing out
**note this is now not my IP address**

""$ ping myhost.dyndns.org
PING myhost.dyndns.org (80.6.206.49) 56(84) bytes of data.

--- myhost.dyndns.org ping statistics ---
11 packets transmitted, 0 received, 100% packet loss, time 9997ms""

Jon T · 08-05-2008, 19:14

Thought i'd read it wrong!

Edit: Just deleted a load of stuff about me pinging the ip in the post, didn't read it properly.

martin28uk · 08-05-2008, 19:18

Quote:

Originally Posted by Jon T

Thought i'd read it wrong!

You need to blank your IP address out in your last post, not a good idea to leave it visible.

BTW, I can't ping it either.

A tracert gets as far as your UBR and then stops.

Thats not my current IP address it changed today when i rebooted my modem upon adding the different router.

But the problem is still present with m new IP 80.6.202.**

Jon T · 08-05-2008, 19:26

When your somewhere with a differnet connection(tomorrow?), run a tracert from a command prompt to your IP address, it will tell you where the connection is failing.

And yes, sorry, I did not read your post properly, i've edited mine.

martin28uk · 08-05-2008, 20:31

Quote:

Originally Posted by Jon T

When your somewhere with a differnet connection(tomorrow?), run a tracert from a command prompt to your IP address, it will tell you where the connection is failing.

And yes, sorry, I did not read your post properly, i've edited mine.

will do thanks for your help

martin28uk · 09-05-2008, 18:43

an update to this problem, looks as if my router is to blame as replacing it temporarily with a not so good basic model resolved me being able to ping externally etc.

Thanks to all that contributed especially Jon T rep added m8

I will update this tread once i get things sorted 100% and after the new router is installed