Linux – SSH + LDAP + pam_groupdn problem

ldaplinuxopenldappamssh

I managed to install SSH + LDAP, moreover I authenticate users through pam_groupdn – if an user is in appropriate group, he is allowed to login to server.

This is part of my pam.d

account sufficient      pam_ldap.so
account sufficient      pam_unix.so

Part of pam_ldap.conf

# Group to enforce membership of
pam_groupdn cn=ldapclient,ou=group,dc=aaaa,dc=zzzz

# Group member attribute
pam_member_attribute memberUid

If I disable pam_unix.so everything is going ok. User is denied if he is not in the group. But I cannot have pam_unix.so disabled, because if LDAP server is offline I would have serious problems to log in, even locally.

If pam_unix.so is enabled:

gigi@0's password: 
You must be a memberUid of cn=ldapclient,ou=group,dc=aaaa,dc=zzzz to login.
Linux testing 2.6.26-2-686 #1 SMP Thu Sep 16 19:35:51 UTC 2010 i686
....

and the user is allowed to login , even though he is not in the group.

I found some solution with /etc/security/access.conf but I would like to avoid this. Any help ?

Thank you, Martin

Best Answer

I resolved it. The problem caused the f*cking nscd caching daemon !!!! I highly recommend to uninstall it while testing.

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Copy your keys to the target server:

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Now try logging into the machine, with ssh 'id@server', and check-in:

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Note: If you don't have .ssh dir and authorized_keys file, you need to create it first

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SSH – Bad Owner or Permissions on ~/.ssh/config

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private keys (ex: `id_rsa`) (code)	0600 (-rw-------)
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public keys (*.pub ex: `id_rsa.pub`)	0644 (-rw-r--r--)
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openssh check-perm.c
openssh readconf.c
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