ssh-key exchange with remote server for password less authentification

long time ago with no update, ok - i guess its a good day to do some.. :p

most it-admins are confronted with doing some ssh-sessions to their remote servers.

time costs money, so if u like to get more comfortable with connecting to them, here is a little tutorial from me that will treat ssh authentification with public keys.

on the ssh-client: ( im currently logged in with my root acc )

#cd .ssh/

#ssh-keygen      # will generate your public key

#cat *.pub | ssh root@IP-of-RemoteServer 'umask 077; cat >>.ssh/authorized_keys2' 

after all your public key will be copied to the remote host.

on the remote-host:

edit your /etc/ssh/sshd_config

be sure that the following options are enabled.

PubkeyAuthentication yes

AuthorizedKeysFile  ~/.ssh/authorized_keys2   # the key path should be the same like on the client

to test your setup, just do a ssh username@RemoteServer

from now you shouldnt be asked for a user / pass.

IPKG for Synology DS213+

CAUTION: before upgrading your DSM disable IPKG ( if its already installed )! 

=> /etc/rc.local

original source: http://www.synology-wiki.de/index.php/IPKG

Install IPKG:

ssh onto NAS

ssh root@NAS

afterwards change to root dir

cd /volume1/

Remote Sniffertrace with tcpdump and netcat

sometimes there is the need to capture network traffic on a remote host, but the host hasn't got enough disk space or resources to handle the traffic. for this issue we can work with a remote capture host using netcat and tcpdump!

Situation: 1x Client ( local ) - 1x Server ( remote )

netcat has to be installed on the local client and the syntax should be as follow:

Opsview with Heartbeat(linux-ha) and drbd on Cent OS 5.5

after spending many hours in reading and reading on howto setup a fully functional working opsview instance on CentOS 5.5, i finally document everything ..


opsview is a product of http://www.opsview.com

INSTALL CentOS

We have two servers with two NICs. One NIC is for the heartbeat and the other to connect to the nework. We synchronize the Database via mysql-Replikation. First you need to Setup centOS on both servers. We parted our300GB harddisk like this. You can keep it like this.