CentOS 5.2 SSH problems

[vignesh2004]

Good Day Everyone,
I'm facing a small problem and hoping you guys can help fix it,

I'm currently running centos 5.2 64 bit, on kernel 2.6.18-92.el5.centos and everything was working ok until I created subinterfaces under my bond0 for multiple vlan support.

The problem now is that I'm neither able to ssh, nor ISCSI works, nor my clustering works ( looks like all of em are related)
However on centos 5.5 I do not seem to have this problem ( I haven't testes this on 5.3 or 5.4)

For ssh,
the server logs say
connection from x.x.x.x
DID NOT RECEIVE IDENTIFICATION STRING FROM UNKNOWN

on the client side it says:
KEX_INIT sent

host disconnected

obviously both client and server are not receiving the handshake packets which led me to believe there's some problem with the network, however said earlier, it works absolutely fine on centos 5.5 with the exact same network configuration.

Can anyone suggest any kernel tweaks on 2.6.18-92 that can enable this for me please?

Thanks,
Vignesh

[gerald_clark]

You have not given us any useful information except that you are using a kernel that has not been supported for years.
CentOS 5 is currently at 5.9 with a kernel version of 2.6.18-348.6.1.el5.

[vignesh2004]

Hi Gerald,

Unfortunately I cannot upgrade beyond centos 5.2 because my backend applications will not support it,

Sorry about the lack of information,
Please find the logs below..

ssh -vvv x.x.x.x
OpenSSH_4.3p2, OpenSSL 0.9.8e-fips-rhel5 01 Jul 2008
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options for *
debug2: ssh_connect: needpriv 0
debug1: Connecting to x.x.x.x port 22.
debug1: Connection established.
debug1: permanently_set_uid: 0/0
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
debug1: loaded 3 keys
debug1: Remote protocol version 2.0, remote software version OpenSSH_4.3
debug1: match: OpenSSH_4.3 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_4.3
debug2: fd 3 setting O_NONBLOCK
debug1: SSH2_MSG_KEXINIT sent

Host disconnected,

On the server side,
It says
Debug1: inetd sockets after dupping 3,3
Connection from xxxx on port xx

and blank then,
My guess is the server refuses to recieve any authentication packets fro the client,

Thanks for all the help in advance,


Thanks,
Vignesh

[TrevorH]

You really need to go and nag your application provider to support something more recent. CentOS 5.2 is now approaching 4 years old and has so many security vulnerabilities that anyone could do anything they liked with your machine with really very little effort.