Geekzone: technology news, blogs, forums
Guest
Welcome Guest.
You haven't logged in yet. If you don't have an account you can register now.


4648 posts

Uber Geek
+1 received by user: 987

Moderator
Trusted
Lifetime subscriber

Topic # 57326 9-Feb-2010 20:17
Send private message

Hey, I'm curious about this more than anything, maybe some network guru can give me an answer.

I've got a server on my home network that I access at home and remotely. At home I use the internal IP or DNS name to get into it using RDP. Externally I use my dyndns domain name to get to my router, which then NATs me in to it. 

I'm just curious - since my dyndns details are configured on my adsl router, is it smart enough to know if the RDP request is coming from the internal or external network?

For example: If I RDP the server from within my home network will the request go out to the internet and then come back in through dyndns to my router then my server? Or will the request go to my router, which then see's the dyndns request and routes it internally before it goes to the internet? 

The reason I ask is that I often choose my Home shortcut instead of my Remote one while I'm out and about, or vice versa if I'm at home. If I can delete the Home one altogether and just use the dyndns shortcut that would save me some frustration   Also I don't want to have to use my internet bandwidth to RDP the server from home if I can help it - hence the home shortcut and this question in general!

What do you think?

Create new topic
BDFL - Memuneh
61192 posts

Uber Geek
+1 received by user: 11974

Administrator
Trusted
Geekzone
Lifetime subscriber

  Reply # 297499 9-Feb-2010 20:52
Send private message

It depends on the router. Most routers won't be smart enough to route back to the LAN if they detect the IP is the one assigned to itself.

My suggestion? Forget about RDP, install LogmeIn Free (www.logmein.com...) and connect from anywhere, no port foward, more than one PC per LAN, etc.




3535 posts

Uber Geek
+1 received by user: 125

Trusted

  Reply # 297503 9-Feb-2010 21:02
Send private message

gehenna: For example: If I RDP the server from within my home network will the request go out to the internet and then come back in through dyndns to my router then my server? Or will the request go to my router, which then see's the dyndns request and routes it internally before it goes to the internet? 

I have a LinkSys router and it is smart enough to do what you say i.e. if I access my Desktop PC via VNC from within the LAN, using the external IP address (assigned using DynDNS), the router sees that the IP address used is assigned to its WAN port, so it routes the traffic directly, without going via the internet.  I can tell this, because the WAN light on the router doesn't flash.

However, I still have two shortcuts set up on my laptop for VNC, one via the LAN and one via the DynDNS address, because that way I can configure the connection appropriately for use via the internet (with a restricted colour pallette) or via the LAN (with a full colour pallette).  Then when I'm away from home, I'm not using unnecessary data traffic via my Mobile Broadband modem.





BDFL - Memuneh
61192 posts

Uber Geek
+1 received by user: 11974

Administrator
Trusted
Geekzone
Lifetime subscriber

3535 posts

Uber Geek
+1 received by user: 125

Trusted

  Reply # 297544 9-Feb-2010 22:55
Send private message

Just the stock firmware that came with the router. I never changed it since buying it in Oct 07.





25 posts

Geek


  Reply # 297600 10-Feb-2010 10:59
Send private message

I think that the router route the packets to internet...Because must to know what IP address belong to xxxx.dyndns.org from the dyndns.org homepage... Forward the request to those DNS and establish the connection in the WAN port....And (i'm not sure) the router never send/receibe the packets in the same inteface..
(sorry about my english i'm from Argentina...)


8027 posts

Uber Geek
+1 received by user: 387

Trusted
Subscriber

  Reply # 297676 10-Feb-2010 14:52
Send private message

Many routers support NAT loopback in their stock firmware in addition DD-WRT, Tomato and OpenWRT do also.

Dyndns conveniently has a support page about loopback problems with some alternative solutions if your router doesn't support NAT loopback
http://www.dyndns.com/support/...


1 post

Wannabe Geek


  Reply # 297841 11-Feb-2010 02:16
Send private message

Most Linksys routers will handle the Loopbacks with your NAT properly so you should be able to use just the one shortcut. 

IRT the mention about our loopback issue article, it essentially talks about how to edit your hosts file so you can have your hostname resolve to your internal IP, instead of going through the router, when you are on your LAN but that's really for desktops that remain on the LAN.





4648 posts

Uber Geek
+1 received by user: 987

Moderator
Trusted
Lifetime subscriber

  Reply # 298034 11-Feb-2010 17:28
Send private message

Turns out after doing some traceroutes and some other sniffing that my router is capable of it as well, it basically routes from internal interface, to external and back to internal all on this side of the network. Quite cool really.

Logmein is fine and I use it here and there to administer family computers but it's not really suitable for what I need to do here on my own server.

734 posts

Ultimate Geek
+1 received by user: 130


  Reply # 299511 16-Feb-2010 14:49
Send private message

IMHO, it's more 'sexy' to avoid middle-men third parties, such as logmein, when it comes to connecting home-to-road PC's and networks.

But that's just me enjoying the features and freedom of dd-wrt, putty and openssh - fun times!

1984 posts

Uber Geek
+1 received by user: 133

Trusted

  Reply # 300967 22-Feb-2010 12:52
Send private message

The DNS resolves a name to the router's external IP address, so if you go to that IP address from inside your LAN then you always get to the router and no further (although the DNS resolution is done on internet). A lot of routers dont do NAT loopback like yours does, but still pointless to rely on DNS for a local address that doesnt change. The local address still works even if your internet isnt stable.




Qualified in business, certified in fibre, stuck in copper, have to keep going  ^_^

Create new topic

Twitter »

Follow us to receive Twitter updates when new discussions are posted in our forums:



Follow us to receive Twitter updates when news items and blogs are posted in our frontpage:



Follow us to receive Twitter updates when tech item prices are listed in our price comparison site:



Geekzone Live »

Try automatic live updates from Geekzone directly in your browser, without refreshing the page, with Geekzone Live now.



Are you subscribed to our RSS feed? You can download the latest headlines and summaries from our stories directly to your computer or smartphone by using a feed reader.

Alternatively, you can receive a daily email with Geekzone updates.