Wireless Access

We test the VMC AOS8.3 on local network and Internet ,and found some problem as follow:

1.When you input show netstat | include tcp, you will see all of the followed Tcp service, you can not see the FTP port 21 inside.

but you indeed can access the TCP port from local network by input the command " Telnet 192.168.100.70 21"  192.168.100.70 is our local network address on VMC

2.OK know we put this VMC on Internet Public IP 47.104.193.111

we input the followed command

"telnet 47.104.193.111 21"  Failed

"telnet 47.104.193.111 873"   OK

"telnet 47.104.193.111 1723" OK

All of the Servise list in show netstat are work well, but ftp port 21 is work in local network only, we are not sure if it work in Internet ?

Are there any body can help to check the reason ?

In general, controllers are supposed to function on the local LAN.  If they are accessed over the internet, it would be because an access point, a client, or another controller sets up a VPN tunnel to that controller and communicates with that controller over the tunnel.

 FTP is restricted to upgrading access point images, and only an access point on the local lan or a remote access point through a VPN tunnel would be accessing the FTP service on the controller.

Dear cjoseph

We are very happy to get your reply. Thanks 

1.We are just test the port and service , we just want to know if they are work well.

2.We know the ap are upgrade by tftp udp 69 usually, but we can hardly test the udp port from Internet, and we also know netcat can test udp but it's result maybe not right, we test the udp 69  by netcat, it is work well 

C:
etcat>nc -uvc 47.104.193.111 69
47.104.193.111: inverse host lookup failed: h_errno 11004: NO_DATA
(UNKNOWN) [47.104.193.111] 69 (tftp) open

3.We khow Tcp service can be test by telnet,So we try to test if the ftp port 21 are work well on our VMC ? 

C:
etcat>telnet 47.104.193.111 21
47.104.193.111...21: failed  (we delete the Chinese words here)

So we think of if the TCP port 21 are work now ?

We are very happy to get your reply. Thanks 

1.We are just test the port and service , we just want to know if they are work well.

2.We know the ap are upgrade by tftp udp 69 usually, but we can hardly test the udp port from Internet, and we also know netcat can test udp but it's result maybe not right, we test the udp 69  by netcat, it is work well 

C:
etcat>nc -uvc 47.104.193.111 69
47.104.193.111: inverse host lookup failed: h_errno 11004: NO_DATA
(UNKNOWN) [47.104.193.111] 69 (tftp) open

3.We khow Tcp service can be test by telnet,So we try to test if the ftp port 21 are work well on our VMC ? 

C:
etcat>telnet 47.104.193.111 21
47.104.193.111...21: failed  (we delete the Chinese words here)

So we think of if the TCP port 21 are work now ?

So we need to know If there are any body can access the TCP ort 21 from Internet on VMC by telnet xx.xx.xx.xx 21 ? 

We can get reply from local netowrk, but no reply from Internet, So we ask this question here to see if anybody know the reason ?