IF (21 || 23) Then 1319?

Joe Hebert

I have a strange connection issue and I?m hoping someone can shed some light on this.

I have a job that I connect to remotely via port forwarding (I know VPN Is much better but port forwarding is what I have to work with for this job.)

Ports 21, 23, and 1319 are forwarded to the main NI master.

The only time I can connect to the master with Netlinx Studio is if I already have a telnet connection established (via a Windoze command prompt) or if I already have an FTP connection established (via Firefox FireFTP.)

If I try to connect with NS2 without establishing a telnet or FTP connection first, the master is found but I get a connection failure after the countdown message as shown in the image below.

Once I?m connected with NS2, I can disconnect the telnet session and/or FTP session and NS2 is still okay. But if I stop communications with NS2 and then try to connect it will fail until I make a telnet or FTP connection again.

This is completely repeatable and rebooting anything doesn?t help. The "Automatically ping the master controller to ensure availability" checkbox is not checked.

Has anyone run into this situation before? Any ideas on what's going on?

Thanks.

bcirrisi

I've had a similar issue when the 'Automatically Ping the Master Controller to Ensure Availability' (in the NetLinx Studio communication settings) is checked. As a habit now, I leave it un-checked whenever I go over the internet.

Joe Hebert

bcirrisi wrote: »

I've had a similar issue when the 'Automatically Ping the Master Controller to Ensure Availability' (in the NetLinx Studio communication settings) is checked. As a habit now, I leave it un-checked whenever I go over the internet.

Same here, I never have the box checked and don't have it checked in this case either.

me wrote:

The "Automatically ping the master controller to ensure availability" checkbox is not checked.

vining

I've had similar situations on my local network too. If I opened debug or diagnostics I could then connect and do a file transfer but if I went straight to file xfer I couldn't connect. Or something like that.

a_riot42

What kind of router are you using?
Paul

Joe Hebert

a_riot42 wrote: »

What kind of router are you using?

I'm not sure what they have in place but I will try to find out. Have you seen certain routers cause this kind of problem?

a_riot42

Joe Hebert wrote: »

I'm not sure what they have in place but I will try to find out. Have you seen certain routers cause this kind of problem?

I have noticed weird behavior when port triggering is used on the cheaper routers.
Paul