Tip & How-To about Computers & Internet

Virtual Server / Port Forwarding does not work from within the Local Network

When you use port forwarding in Virtual Servers and try to test it from within the local network, it may fail. When for example, port 80 is forwarded to a web server in the local network, you may get the router's home page instead of the web server's one or you may get nothing at all. When you try to use the server from outside the local network it will work fine though.

This can happen when you try to access the router's WAN IP address from within the local network. In order for port forwarding to work from within the local network, the router needs to support a feature called NAT loopback. This is not a part of the specification of Belkin routers and modem-routers, so most of them will not have the feature, and if a router does have it, it is not supported.

In order to use the server from within the LAN, you can address it by its internal LAN IP address (e.g. 192.168.2.101).

If the WAN IP address has a DNS host name associated with it, such as www.example.com, and you need to use that name to connect to the server, you can do so by associating the name to the local IP address in the hosts file (a file called hosts with no extension). This file lists IP addresses and host names and is used before actual DNS lookups are done. You can add lines to the hosts file using a text editor like Notepad on Windows. The lines look like:

192.168.2.101 www.example.com www.otherdomain.com # comment

The lines contain an IP address and one or more host names separated by white space. Anything that follows a hash sign is a comment and will be ignored. You will need to change the hosts file on all machines in the LAN that need access to the server.

On Windows, the hosts file can be found in C:\Windows\System32\Drivers\Etc on Windows XP, Vista and Windows 7, in C:\WinNT\System32\Drivers\Etc on Windows 2000, and in C:\Windows on Windows 98 and ME. You need to have administrator rights to edit the file; on Windows Vista and Windows 7 you need to run Notepad as administrator.

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1 Answer

how can i configure aip w505 for att elevate internet, in order to view my qc dvr


You need to enable the virtual server settings on the AIPW505
You also need to allocate a static address to the DVR within the range of the DHCP address range.
Virtual Server Settings - Selects between enabling or disabling port
forwarding the virtual server. (Default: Disable)
? IP Address - Specifies the IP address on the local network to allow external access.
? Port Range - Specifies the port range through which traffic is
forwarded.
? Protocol - Specifies a protocol to use for port forwarding, either TCP,UDP or TCP&UDP.
? Comment - Enter a useful comment to help identify the forwarded
port service on the network..
The manual can be obtained from here
ALFA NETWORK Inc

Oct 21, 2012 | ADVANCE Alfa AIP-W505 802.11n/b/g Wireless...

1 Answer

Port Forwarding on NB7Plus4W router


Some times you will need to open the Logical Ports on the router.
These are the logical ports.
For this you will need to open the set up interface of the router.
Once you open the set up interface of the router, you will be able to find the settings on the router where you can open the ports for the particular program.

If you are opening the ports for a special device in your network, then you must know the IP address of that device.
For example, wireless camera, DVR, X-box, Play station ...
You can choose the option PORT FORWARDING for a special device application.
If you just want to open the ports for all the network, then you can choose PORT TRIGGERING



For example ,
You have a Linksys wireless router and you want to open the ports for the X-box.
You have opened the set up interface of the router. You will see Application and Gaming TAB at the top.
If you click on that tab you will find different Sub tabs.
Click on Port Triggering => Here you can open the port numbers for the network.
Click On Port forwarding if you want to open the ports for a special device in the network.
Click Save settings once you open the ports on the router.

Some of the recommended port numbers for different applications :

IMAP ==> 143 SMTP : 25
HTTPS ==> 443 HTTP : 80
DNS ==> 53 FTP : 21
SNMP ==> 161 TELNET : 23
XBOX ==> 53, 80-88, 3074
PS3 ==> 80, 443-447 ,5223, 3478-3479, 3658, 10070-10080.
WII ==> 28910, 29900, 29901, 29920, 80, 443
VPN ==> 1723, 500, 443-447, 10000-20000
World of Wars ==> 3724, 6112, 6881 - 6999
Click Here for more info

Nov 22, 2009 | NetComm NB5PLUS4W Wireless Router

1 Answer

2wire 2701 block port 80


Go to the following link. This is just an example on how to forward ports for limewire. Use the same steps to forward port 80.

http://portforward.com/english/routers/port_forwarding/2wire/2701HG-B/Limewire.htm

If it still doesnt work, try updading the firmware. In case this fails, then we have some issue with the router

regards

Sandeep

Oct 13, 2009 | 2wire 2700HG-B Router (2700HGB)

1 Answer

Linksys WRT54 GC failed auto port forwarding


check in your pana sonic ipadreses then test in your network can you able ping of ip of cam?

If you can get ping and if you save ip forwarding port 80 to cam ip then check in camera that the settings of "access via interent is enabled" then you cana cces it with cam ip with 80 http port.

Jul 27, 2009 | Linksys WRT54GC Wireless Router

3 Answers

port forwading


http://portforward.com/
this site may be of some assistance

Jun 19, 2008 | Computers & Internet

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