Question: How do you check if a port is open when you cannot use telnet or install Cacti? I want to see if a port is open between two Linux servers. Telnet isn't installed. I tried this command: 

```
cat < /dev/tcp/x.x.x.x/6061

```

where x.x.x.x was the remote IP address of the Linux server and port 6061 is the port that I want to test. But based on tests of known working and not working ports, this command wasn't conclusive to me. There may be an environmental explanation for that.

Answer: 
Install nmap and than:

```
nmap x.x.x.x

```
Better use (if installed) : [netcat](/questions/tagged/netcat "show questions tagged 'netcat'") :

```
nc -zw3 <host> <port>

```

If you want to use the [bash](/questions/tagged/bash "show questions tagged 'bash'") feature *net redirection* :

```
cat < /dev/tcp/x.x.x.x/6061

```

do it the right way :

```
{ exec 3<> /dev/tcp/127.0.0.1/6061; } &>/dev/null &&
    echo "Connection to socket OK" ||
    echo >&2 "Can't connect"

```

If it doesn't work, you need to compile [bash](/questions/tagged/bash "show questions tagged 'bash'") with `--enable-net-redirections`