[Eisfair] BackupZip Rsync c3bcber SSH: SSH Login erfolgreich angemeldet2c aber Backup schlc3a4gt fehl

[Marcus Roeckrath]

Hallo,

Armin Weinmann wrote:

>   4   Activate ssh Login
> 
> den SSH Login aktiviere geht alles problemlos, am Schluss kommt eine
> Erfolgsmeldung. Wenn der Job dann per CRON gestartet wird kommen zwei
> Mails mit Fehlermeldungen:

Wie ich nun durch Zufall festgestellt habe, beinhaltet unser eisfair schon
immer ein Skript (zu openssl gehörig), dass Pub-Keys auf entfernte Rechner
überträgt:

eis # ssh-copy-id -?
Usage: /usr/bin/ssh-copy-id [-h|-?|-n] [-i [identity_file]] [-p port] [[-o
<ssh -o options>] ...] [user@]hos

Hier noch die manpage dazu:

SSH-COPY-ID(1)                         BSD General Commands Manual                        
SSH-COPY-ID(1)

NAME
     ssh-copy-id — use locally available keys to authorise logins on a
remote machine

SYNOPSIS
     ssh-copy-id [-n] [-i [identity_file]] [-p port] [-o ssh_option]
[user@]hostname
     ssh-copy-id -h | -?

DESCRIPTION
     ssh-copy-id is a script that uses ssh(1) to log into a remote machine
(presumably using a login
     password, so password authentication should be enabled, unless you've
done some clever use of multi-
     ple identities).  It assembles a list of one or more fingerprints (as
described below) and tries to
     log in with each key, to see if any of them are already installed (of
course, if you are not using
     ssh-agent(1) this may result in you being repeatedly prompted for
pass-phrases).  It then assembles
     a list of those that failed to log in, and using ssh, enables logins
with those keys on the remote
     server.  By default it adds the keys by appending them to the remote
user's ~/.ssh/authorized_keys
     (creating the file, and directory, if necessary).  It is also capable
of detecting if the remote
     system is a NetScreen, and using its ‘set ssh pka-dsa key ...’ command
instead.

     The options are as follows:

     -i identity_file
             Use only the key(s) contained in identity_file (rather than
looking for identities via
             ssh-add(1) or in the default_ID_file).  If the filename does
not end in .pub this is added.
             If the filename is omitted, the default_ID_file is used.

             Note that this can be used to ensure that the keys copied have
the comment one prefers
             and/or extra options applied, by ensuring that the key file has
these set as preferred
             before the copy is attempted.

     -n      do a dry-run.  Instead of installing keys on the remote system
simply prints the key(s) that
             would have been installed.

     -h, -?  Print Usage summary

     -p port, -o ssh_option
             These two options are simply passed through untouched, along
with their argument, to allow
             one to set the port or other ssh(1) options, respectively.

             Rather than specifying these as command line options, it is
often better to use (per-host)
             settings in ssh(1)'s configuration file: ssh_config(5).

     Default behaviour without -i, is to check if ‘ssh-add -L’ provides any
output, and if so those keys
     are used.  Note that this results in the comment on the key being the
filename that was given to
     ssh-add(1) when the key was loaded into your ssh-agent(1) rather than
the comment contained in that
     file, which is a bit of a shame.  Otherwise, if ssh-add(1) provides no
keys contents of the
     default_ID_file will be used.

     The default_ID_file is the most recent file that matches:
~/.ssh/id*.pub, (excluding those that
     match ~/.ssh/*-cert.pub) so if you create a key that is not the one you
want ssh-copy-id to use,
     just use touch(1) on your preferred key's .pub file to reinstate it as
the most recent.

EXAMPLES
     If you have already installed keys from one system on a lot of remote
hosts, and you then create a
     new key, on a new client machine, say, it can be difficult to keep
track of which systems on which
     you've installed the new key.  One way of dealing with this is to load
both the new key and old
     key(s) into your ssh-agent(1).  Load the new key first, without the -c
option, then load one or more
     old keys into the agent, possibly by ssh-ing to the client machine that
has that old key, using the
     -A option to allow agent forwarding:

           user at newclient$ ssh-add
           user at newclient$ ssh -A old.client
           user at oldl$ ssh-add -c
           ... prompt for pass-phrase ...
           user at old$ logoff
           user at newclient$ ssh someserver

     now, if the new key is installed on the server, you'll be allowed in
unprompted, whereas if you only
     have the old key(s) enabled, you'll be asked for confirmation, which is
your cue to log back out and
     run

           user at newclient$ ssh-copy-id -i someserver

     The reason you might want to specify the -i option in this case is to
ensure that the comment on the
     installed key is the one from the .pub file, rather than just the
filename that was loaded into you
     agent.  It also ensures that only the id you intended is installed,
rather than all the keys that
     you have in your ssh-agent(1).  Of course, you can specify another id,
or use the contents of the
     ssh-agent(1) as you prefer.

     Having mentioned ssh-add(1)'s -c option, you might consider using this
whenever using agent forward-
     ing to avoid your key being hijacked, but it is much better to instead
use ssh(1)'s ProxyCommand and
     -W option, to bounce through remote servers while always doing direct
end-to-end authentication.
     This way the middle hop(s) don't get access to your ssh-agent(1).  A
web search for ‘ssh
     proxycommand nc’ should prove enlightening (N.B. the modern approach is
to use the -W option, rather
     than nc(1)).


-- 
Gruss Marcus