following error msg displayed
- getaddrinfo 'Jack_s-server' error: Name or service not known
- error: unable to determine IP address of "Jack_s-server'
- error: no valid servers configured
- Fatal: error processing configureation file '/etc/proftpd.con'

How can I fix it. Please help.

P.S. I have a router.. What Can i do?

it is another kind of problem. doesn't relate with your router.
think u better start from using their sample configuration, slowly modify, analysze and debug.
that should be easier since your debug information is rather lack of;

it sounds like u defined hostname as Jack_s-server in proftpd.conf. or u did change your hotsname and didnt add record in /etc/hosts file about new hotname.

u can change the servername or hostname to localhost in proftpd.conf
or add a record in /etc/hosts file to proftpd find ip of "Jack_s-server":
good luck.

Hey.. thx for helping.. But I feel really sorry.. because I don't really understand how am I supposed to do it in order to make proftpd to recognize my hostname. I am a true Newbie so please explain more in detail.

Use your favorite text editor and open the contents of this file:

Copy and paste the contents of this file here.
Now granted that there is nothing wrong with that file, let's start with a fresh proftpd.conf:

Copy and paste the lines above into a new proftpd.conf file...replace your old one with this new one. Restart profptd.

for /etc/hosts, is it supposed to be empty. I have slackware 10.0, and it has hosts.allow and hosts.deny. which hosts is the one I am supposed to do editing.
Or, should both files be empty?

Umm..no, /etc/hosts is NOT supposed to be empty. We need to fix this.

The easiest way is to just start your network config all over with the netconfig tool. Give your machine a hostname with a bogus domain like "local.lan". Reboot and let's finish fixing your proftpd.

Hello.. netconfig seems resolved the ip problem, but I proftpd -c /etc/proftpd.conf, it seems to work. When I check ps -l, proftpd is not on the list. I tried to ftp localhost, it says "Services is not available, and remote server has closed connection." then it turns to ftp> promotion.
How can solve this?

You cannot start proftpd in that manner with the default Slackware configuration. The default configuration is for running from inetd.

If you haven't done so already, replace your existing /etc/proftpd.conf file with the one I posted above. This will allow you to run proftpd from the command line (standalone mode).

Then to test it, do this:

If successfull, the cursor should return with the Proftpd credentials, and sit there asking for a name. Login with a user/pass on that system (if you've created one).

I did exactly what you asked to do..but I get the same result. when I ftp my internal ip address, the same thing happened. The connection is closed ...what else can I do?

post the output of following commands:
cat /etc/hosts
hostname

127.0.0.1 Localhost
127.0.0.1 darkstar.com darkstar

change /etc/hosts file like that:
and try to run proftpd.

good luck.

This shows that you are obtaining your IP from a DHCP server (?).

Let's check some things:

1.) Is proftpd running from inetd? Did you edit /etc/inetd in any way prior to trying proftpd?

2.) When you started proftpd with the config file I gave you, did it return any errors? If you do "#ps -A | grep proftpd", is proftpd listed in the return output?

3.) What is your internal IP address (where is the DHCP server in relation to you? Are you on a broadband connection of some kind?)

4.) After you've started proftpd, do this:

If proftpd is really running, then your prompt should return with a line that looks like this:

5.) If you are seeing this line and you know proftpd is running, then try