Two PCes in a network, one Debian 4.0 r1, another Centos 5.0. I can connect from debian to centos via ssh but when I want to connect from centos to debian connection is not working. I get message "ssh: connect to host 10.100.250.253 port 22: Connection refused".
Ping works fine. In /etc/sshd_conf I have AllowRoot yes, in /etc/hosts_allow and denny I have nothing. No firewall is running. What could be the reason?

Thanks
Mario

at the moment connection is working :-). I have no idea what was wrong.

this machine gets me crazy, no it's not working again :-(((((.

For a start, disable that -- set it to AllowRoot no and do it now. There is absolutely no sane reason to allow remote root logins trough SSH, unless you want trouble (maybe not even then). You can just as well log in as a regular user and then use sudo to do things with root privileges, or maybe 'su' to become root if you don't know how to use sudo. But allowing root logins trough SSH means that anybody can start easily guessing your root password (brute-force ssh-login attack is a very simple and ugly way of doing that, for example; preventing direct root logins disables this kind of attack to determine root password).

Nevertheless it sounds odd. Are you sure the network connection is fine all the time? If
shows empty tables (=no firewall), you don't have any external firewalls between the machines, the hosts allow/deny files are empty and you have sshd running without problems, I can't think of much else. I'd read trough the sshd configuration file to make sure there are no strange settings, and test the connection well.

/sbin/iptables -L says this


hssdgw:/etc# iptables -L
Chain INPUT (policy ACCEPT)
target prot opt source destination

Chain FORWARD (policy ACCEPT)
target prot opt source destination

Chain OUTPUT (policy ACCEPT)
target prot opt source destination


I tried to mount on centos from debina via nfs and also got connection refused. Minute ago I tried again to mount and it works. Then I tried ssh, now it also working. But for how long? It already happened that it works for some time and then it stop :-(. Ping works always.
Is ther any network log file? It seems it's not just a ssh problem but network.

Thanks for helping me.
Mario

Dear

Please check the /root/.ssh/know_hosts file if you are trying with root user.
Some times due to old entry of ssh host keys you will not able to get login.

check this file and if you find any appropriate entry then you can remove it and then try, it will work.

I think it not the problem of ssh but something with network. I also tried to mount via nfs

[root@sigw tmp]# mount -t nfs 10.100.250.253:/export /import/
mount: mount to NFS server '10.100.250.253' failed: System Error: Connection refused.

NFS deamon on 10.100.250.253 is running ok. I managed to mount it few times, just like I connect via ssh sometimes.

Connection from debian machine to centos machine is working ok via ssh.

the problem was another pc in the network with he same ip like my debian :-(.

Mario