Remote Desktop doesn't work from inside my local town

Redgie

Redgie

Redgie

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Right I've asked about this before but I think I've narrowed it down a bit better.

I have a DynDNS account set up to allow me to remote into my home server from anywhere, which is great when I'm in work / on jobs in case I need to access files, settings, downloads etc. Now this used to work perfectly every time, open RDP, remote into the hostname and connects straight away.

Now though, if I try it from inside my local town from a normal ADSL broadband, it only works 5% of the time, usually around midday. However, if I try from my sisters house in my local town, who uses fibre optic broadband (Virgin) it works 100% of the time.

Also, if I try to remote in from outside of my local town, as far or as close as I want, it works 100% of the time.

What on earth is causing this problem? I've been in touch with o2 who refuse to acknowledge a problem, and it does work a small percentage of the time. But as I only ever work in my local town, I can never use RDP!

Please help OcUK gods :(

EDIT: Router is a Netgear DG834GT with DGTeam firmware on (The latest) and has no blocked addresses on it.
 
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It sounds like it might be an issue with DNS TTLs (time to live values) at the various ISPs you are trying.

If your dynamic IP address changes frequently, it will take the internet DNS servers and ISP nameservers a little time to catch up. This can be really fast for good ISPs (less than 15 mins), or really slow for lazy/sloppy ones.
DNS propogation is a pain in the butt.

How often does your public IP address change?
 
Thanks for the info, that's a much better theory than anything I've had so far!

As for how often does my IP chance, not particularly often, hard to put a timescale on it because it is so random but in the past it's remained the same for months at a time?

The ISP at my work and home are both o2, would it be worth changing both routers to use openDNS to see if that makes a difference?
 
sidethink said:
It sounds like it might be an issue with DNS TTLs (time to live values) at the various ISPs you are trying.

If your dynamic IP address changes frequently, it will take the internet DNS servers and ISP nameservers a little time to catch up. This can be really fast for good ISPs (less than 15 mins), or really slow for lazy/sloppy ones.
DNS propogation is a pain in the butt.

How often does your public IP address change?
Click to expand...


Don't think this will be an issue. DynDNS has a deliberately short TTL (20 seconds or 1 minute depending on the account type) which ensures that a lookup is done pretty much "live" to the authoritive server rather than from a cached copy on AN OTHERs DNS server. Can you set the firewall to log and allow the traffic - that way you can determine if the traffic is actually hitting the router the 95% of the time it's failing.
 
I will it set it to log when I get home in half an hour or so and see what I get, thanks :)

Interestingly, sometimes I can RDP into work from home...
 
I attempted a RDP from work just now, I then remoted in via 3G on my phone to check the logs, there is nothing in there from my work at all, which I can only assume means it's not even getting to the router?
 
Daft question, are you sure the machine is 100% on? and hasn't gone to sleep?

What I do is no-ip (same as dyndns) into my router, send a wake packet to my machine, then I connect to it
 
bledd. said:
Daft question, are you sure the machine is 100% on? and hasn't gone to sleep?

What I do is no-ip (same as dyndns) into my router, send a wake packet to my machine, then I connect to it
Click to expand...
knowlton said:
Is it RDP enabled on the receiving router? Sometimes you have to enable the ports to allow it through..
Click to expand...

I can remote in using my phone or a collegues home server, I can definitely say the router is correctly configured and the server is certainly on.
 
assuming you use gmail, you can get recently used IP addresses from the "last activity" link and use that.

edit: you could probably get the IP by logging into your dyndns account as well but it's been years since i've used that.
 
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Do you have a VPN you can use to try and connect ?

Sounds like some sort of routing problem?
 
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marc2003 said:
assuming you use gmail, you can get recently used IP addresses from the "last activity" link and use that.

edit: you could probably get the IP by logging into your dyndns account as well but it's been years since i've used that.
Click to expand...

Why would I need my IP? That doesn't allow me to RDP in either.

cp88 said:
Do you have a VPN you can use to try and connect ?

Sounds like some sort of routing problem?
Click to expand...

I haven't set up a VPN but I doubt I'd be able to due to the connection problems. I have tried VNC to make sure it's not just RDP and VNC doesn't work either.
 
Redgie said:
Why would I need my IP? That doesn't allow me to RDP in either.



I haven't set up a VPN but I doubt I'd be able to due to the connection problems. I have tried VNC to make sure it's not just RDP and VNC doesn't work either.
Click to expand...

I mean a VPN like expat shield/strong VPN, then you wouldn't be connecting from within the same town.
 
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Ahh I see, that would help but it's not really a solution as much as it is an alternate route. I'm looking to (If I can) find out why this is happening and sort it. Thank you though :)
 
Redgie said:
Why would I need my IP? That doesn't allow me to RDP in either.
Click to expand...

if you can't get in via IP then you really are wasting your time thinking it's a DNS issue.... :p

you can of course use nslookup to see if the DNS is working or not. see if it matches your IP. this really should have been mentioned earlier.

open a command prompt:

Code: 
nslookup yourdomain.dyndns.org
 
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Forget the DNS, if you cant connect via your IP then the DNS will fix itself when you can connect again :)
 
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