You receive the error and you don’t exactly know what to do, if this is the first time that you see this error when you add a new client there are mostly two causes of this error:
Backuppc cannot log-in to the client computer, or
rsync path is different on client computer or never installed
and if this is not the first backup of the client, then you most probably have a previous definition of the client in known_hosts file, if you re-installed the client operating system, delete server key from ~backuppc/.ssh/known_hosts file and try to re-login from backuppc terminal:
vi ~backuppc/.ssh/known_hosts #find the corresponding servers old key and delete line by typing "dd", save the file with SHIFT+ZZ (saves and quits) su -l backuppc #login as backuppc ssh root@client_ip_address # and log-in to the client host, save the key by typing yes #use ctrl + D to log out
Above is the easiest way to exchange client hosts public key while confirming backuppc can log in to the client host. First, check if you are able to log in to the client through backuppc user, to do so type from the terminal:
su -l backuppc ssh root@client_ip_address
If you were able to log-in to the server without any password or warnings go to step II, otherwise generate a new ssh key for backuppc (or if you already created one, use it) and add the key to client hosts authorized_keys file. To generate a new backuppc key, use:
#On BackupPC Server ssh-keygen -t rsa cp ~/.ssh/id_rsa.pub ~/.ssh/BackupPC_id_rsa.pub #Switch to client host, copy generated BackupPC_id_rsa.pub to the client with sftp, scp or rsync and touch ~/.ssh/authorized_keys2 # create if it is not there cat BackupPC_id_rsa.pub >> ~/.ssh/authorized_keys2 # add the key
And retry to log in again as described above. Note: If .ssh folder doesn’t exist on the client, simply try to ssh to an arbitrary IP address and cancel the operation, the folder will be created with appropriate permissions. Step II: rsync paths must be identical or defined If you didn’t set rsync path in Host->Edit Config section of Backuppc, Backuppc will look at the default location of rsync, to check the place of rsync on the host, type:
[root@vt ~]# which rsync /usr/bin/rsync [root@vt ~]#
if you don’t have the app “which” simply install it with “yum install which”. If you get a result like “No rsync in …” you probably don’t have rsync installed on your host, to install type “yum install rsync” and check the path again. If rsync exists and not in the same path as BackupPC server, you need to set the location in Host configuration->XFer->RsyncClientPath