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imported>Matthias.neumann
(Änderung 971 von Matthias.neumann (Diskussion) rückgängig gemacht.)
 
imported>Burghardt
 
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Generelle Ansprechparter bei Problemen mit dem Gebäude sind die Hausmeister. Insbesondere gilt das auch bei:
__NOTOC__
 
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* Stromausfall - den Raum mit den Sicherungen können ''nur'' die Hausmeister (bzw. die Elektotechniker) betreten
* Back to [[Shell]]
 
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* ...
   
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{| class="wikitable sortable"
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!Name || Rufnummer || Handy
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|-
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|Nolte || 19781 || *3919781
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|-
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|Stein || 79091 || *3979091
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|-
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|Rudolph|| 8004 || *398004
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|-
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|}
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* '''Meldung von Störungen''' bitte ''erst'' an den Hausmeister, nur in Notfällen an die Störmeldezentrale 1171
   
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=== Andere ===
While older ssh-versions relied on [[MD5]] (Message Digest number five) for generating a fingerprint this is considered "unsafe" for some time now. The current implementation uses [[SHA256]] by default.
 
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* Gwdg: support@gwdg.de -- 201-1523
   
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[[Kategorie:IfI]]
== Current fingerprints as of April 2017 ==
 
 
=== Older Servers ===
 
Included in [[debian]] [[Jessie]], [[Ubuntu]] [[Trusty]] and others. Used ''prior April 10th'' in <tt>login</tt>, <tt>shell</tt> and all pool workstations:
 
<pre>
 
~$ lsb_release -d; for F in /etc/ssh/*.pub ; do echo -e "\n$F:"; ssh-keygen -l -f $F; done
 
Description: Ubuntu 14.04.5 LTS
 
 
/etc/ssh/ssh_host_ecdsa.pub:
 
256 07:84:c9:e1:59:4f:03:75:69:b1:e4:d0:b4:1f:9a:cd root@nfsadm (ECDSA)
 
 
/etc/ssh/ssh_host_ed25519_key.pub:
 
256 93:11:29:c4:a2:03:e1:2d:b1:82:05:74:dd:a5:3b:9a root@nfsadm (ED25519)
 
 
/etc/ssh/ssh_host_rsa_key.pub:
 
2048 de:db:6e:72:52:de:30:73:db:bb:6e:79:df:f9:2c:0d root@nfsadm (RSA)
 
</pre>
 
 
=== Newer Servers ===
 
Included in debian [[Stretch]], Ubuntu [[Xenial]] and others. ''Currently used'' in <tt>login</tt>, <tt>shell</tt> and all pool workstations:
 
<pre>
 
~$ lsb_release -d; for F in /etc/ssh/*.pub ; do echo -e "\n$F:"; ssh-keygen -l -f $F; done
 
Description: Ubuntu 16.04.2 LTS
 
 
/etc/ssh/ssh_host_dsa_key.pub:
 
1024 SHA256:OpBcTf2pc3p3oUXKZvJ2773TULj6lskxYI/INZvLes8 root@c043 (DSA)
 
 
/etc/ssh/ssh_host_ecdsa_key.pub:
 
256 SHA256:IN1YJYjBWzm1irujENh5KVB6RxqXBGbvIT6WrGv++fw root@nfs (ECDSA)
 
 
/etc/ssh/ssh_host_ed25519_key.pub:
 
256 SHA256:P/gxfKUFA/5Gf9v5GOGQhcV3TgNzt9wS+moCKFjlUpo root@c009 (ED25519)
 
 
/etc/ssh/ssh_host_rsa_key.pub:
 
1024 SHA256:f7orU3tn+mVuMlv/CjnfJOF8dr4/VhPhZMtSirMIndQ root@c043 (RSA)
 
</pre>
 
 
If you are using an old client you need to check the deprecated MD5 checksum:
 
<pre>
 
~$ lsb_release -d; for F in /etc/ssh/*.pub ; do echo -e "\n$F:"; ssh-keygen -l -E MD5 -f $F; done
 
Description: Ubuntu 16.04.2 LTS
 
 
/etc/ssh/ssh_host_dsa_key.pub:
 
1024 MD5:c0:e6:ac:3f:62:4c:4e:dc:cc:68:66:45:83:f2:23:9a root@c043 (DSA)
 
 
/etc/ssh/ssh_host_ecdsa_key.pub:
 
256 MD5:1a:04:8e:f5:7e:e6:44:6a:a8:1f:b7:f0:8c:40:f8:ff root@nfs (ECDSA)
 
 
/etc/ssh/ssh_host_ed25519_key.pub:
 
256 MD5:c5:fb:87:6c:78:29:32:90:ea:3d:3c:0d:9b:2c:83:bd root@c009 (ED25519)
 
 
/etc/ssh/ssh_host_rsa_key.pub:
 
1024 MD5:c6:82:13:00:60:c5:70:a7:60:6b:09:8d:c7:0b:b3:06 root@c043 (RSA)
 
</pre>
 
 
== Actually compare a fingerprint when establishing a session ==
 
As a client you need to verify the actually used key/fingerprint to those documented above. Depending on old/new implementations the exact behavior and output might be different:
 
 
=== Using an '''older''' client ===
 
* connecting to an '''old''' server
 
~$ ssh -o VisualHostKey=yes shell.informatik.uni-goettingen.de
 
Host key fingerprint is 07:84:c9:e1:59:4f:03:75:69:b1:e4:d0:b4:1f:9a:cd
 
 
* connecting to a '''newer''' server
 
~$ ssh -o VisualHostKey=yes newerserverinstance.informatik.uni-goettingen
 
Host key fingerprint is 1a:04:8e:f5:7e:e6:44:6a:a8:1f:b7:f0:8c:40:f8:ff
 
 
 
=== Using a '''newer''' client ===
 
* connecting to an '''old''' server
 
~$ ssh -o VisualHostKey=yes shell.informatik.uni-goettingen.de
 
Host key fingerprint is SHA256:L+FCMj2bm8x/BfR8AdaaLnqTmFD35D0EYNlFG7a2dt8
 
 
* connecting to an '''old''' server
 
~$ ssh -o VisualHostKey=yes -o fingerprinthash=md5 shell.informatik.uni-goettingen.de
 
Host key fingerprint is MD5:07:84:c9:e1:59:4f:03:75:69:b1:e4:d0:b4:1f:9a:cd
 
 
* connecting to a '''newer''' server
 
~$ ssh -o VisualHostKey=yes localhost
 
Host key fingerprint is SHA256:IN1YJYjBWzm1irujENh5KVB6RxqXBGbvIT6WrGv++fw
 
 
 
== See also ==
 
* [[Shell]]
 

Version vom 29. Juni 2017, 11:27 Uhr

Generelle Ansprechparter bei Problemen mit dem Gebäude sind die Hausmeister. Insbesondere gilt das auch bei:

  • Stromausfall - den Raum mit den Sicherungen können nur die Hausmeister (bzw. die Elektotechniker) betreten
  • ...
Name Rufnummer Handy
Nolte 19781 *3919781
Stein 79091 *3979091
Rudolph 8004 *398004
  • Meldung von Störungen bitte erst an den Hausmeister, nur in Notfällen an die Störmeldezentrale 1171

Andere

  • Gwdg: support@gwdg.de -- 201-1523