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danteuk
03-05-2007, 01:18 AM
Hi,

I'm live booting on machine with view to doing an HD install
Machine is currently running (almost, refusing to boot anymore) Xandros linux.

Problem:
SSH to the live boot machine(DHCP'd 10.1.0.44 ) doesn't work.
No error message, just ssh hangs forever ( does even show a login prompt )
Tried from a Windows machine using putty and from DamnSmall Linux using just ssh
Both machines can ping 10.1.0.44 and it can ping them.
ssh on 10.1.0.44 to DamnSmall linux machine also hangs ( Window putty to DSL works ).

Netstat on machine shows I have started sshd and it's listening ( 10.1.0.44:ssh *:* LISTEN )
KNOPPIX Firewall is reporting as "Firewall Active? no"
from 10.1.0.44 I can do: ssh 10.1.0.44 and it connects okay.
Running a Port Scan from 10.1.0.44 to 10.1.0.44 shows ssh open.
Running a Port Scan from 10.1.0.44 to DSL machine also shows ssh open.

Any ideas?
Is there another firewall somewhere?

NOTE: Also Icewasel is not able to connect to web server on DSL machine. It's looking like it TCP that's not working a UDP/ICMP is? (ie ping works)
Is it something in the /etc/ssh/sshd-config that I can't spot that's stopping it working?

kirol
03-05-2007, 03:43 PM
you first need to generate host keys and start the daemon with "/etc/init.d/ssh start" (as root).

danteuk
03-05-2007, 04:59 PM
I believe those keys were created when I ran the sshstart script.
In /etc/ssh I have:
moduli
primes
ssh_config
ssh_host_dsa_key
ssh_host_dsa_key.pub
ssh_host_key
ssh_host_key.pub
ssh_host_rsa_key
ssh_host_rsa_key.pub
sshd_config

I reboot and started again and re-run that script, changed root passwd and it's made no difference.
Can still ping but not ssh to or from the live boot machine.

angor
03-06-2007, 09:30 AM
Try ssh -v . This increases the verbosity of the client - perhaps it will tell you what's missing.

danteuk
03-07-2007, 11:01 PM
Good suggestion, not sure if this helps anyone.

This is trying to ssh to the live boot Knoppix 5.1.1 ( Current Linux Mag Cover disk. Issue 77 )
Trying from DamnSmall Linux:
root@0[root]# ssh -v 10.1.0.44
OpenSSH_3.6.1p2 Debian 1:3.6.1p2-9, SSH protocols 1.5/2.0, OpenSSL 0x0090705f
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options for *
debug1: /etc/ssh/ssh_config line 17: Deprecated option "FallBackToRsh"
debug1: /etc/ssh/ssh_config line 18: Deprecated option "UseRsh"
debug1: Rhosts Authentication disabled, originating port will not be trusted.
debug1: Connecting to 10.1.0.44 [10.1.0.44] port 22.
debug1: Connection established.
debug1: read PEM private key done: type DSA
debug1: read PEM private key done: type RSA
debug1: identity file /root/.ssh/identity type -1
debug1: identity file /root/.ssh/id_rsa type -1
debug1: identity file /root/.ssh/id_dsa type -1

Try to go from Knoppix back back to the DamnSmall linux machine:
# ssh -v 10.1.0.10
Basically the lines with errors are:
debug1: An invalid name was supplied
Cannot determine realm for numeric host address

debug1: An invalid name was supplied
A parameter was malformed
Validation error

debug1: SSH2_MSG_KEXINIT sent
-----------------------------------------------------------

Giving the machines names in /etc/hosts made no difference.

angor
03-08-2007, 12:56 PM
>debug1: An invalid name was supplied

I don't know if 'name' means username, but just to make sure try
ssh username@10.1.0.10
where 'username' is a valid account on 10.1.0.10 .

You might also try to step up ssh's verbosity by increasing the amount of 'v's
up to three (ssh -vvv).

Consider running sshd on 10.1.0.10 with -D or -d options (man sshd for details)
to see what's going on on the other side of the connection.

(P.S. I won't be reading this forum before Mon 12th again, just in case you
wonder why I've stopped responding :-)