Magic Triangle, Snow Leopard Server, Lion Clients

Just tried to bind a Lion client to our Magic Triangle infrastructure. Apple describes the problems as: A Mac OS X v10.7 Lion client may be unable to connect to a Mac OS X v10.6 Open Directory Server. This can happen if Lion uses Authenticated Binding to a Mac OS X v10.6 Open Directory Server that is also bound to Active Directory by means of a magic triangle.

Apple’s fix is to use Terminal to run a pair of shell commands on the Snow Leopard Server Open Directory Master Server and Replicas. Apple says:

Note: These commands will turn off GSSAPI authentication for the LDAP Server on the Mac OS X v10.6 Open Directory Master Server and Replicas. The servers will then use CRAM-MD5 authentication.

sudo rm /usr/lib/sasl2/openldap/libgssapiv2.2.so
sudo rm /usr/lib/sasl2/openldap/libgssapiv2.la

Restart the server after making this change.

If you want to restore the original settings, execute these commands:

cd /usr/lib/sasl2/openldap
sudo ln -s ../libgssapiv2.2.so
sudo ln -s ../libgssapiv2.la

Restart the server after making this change.

How to Force Propagation on Apple Secondary DNS Server

As you all probably know that using Apple’s DNS server can be challenging at times. If you make changes on the primary you usually have to wait some time before those changes propagate to the secondaries. However with the following commands you can force this propagation without having to nuke files or folders in /var/named

1. On the secondary server, run this command. (use whatever zone you want to transfer in place of lan.example.com
rndc -p 54 retransfer lan.example.com IN com.apple.ServerAdmin.DNS.public

2. Reload configuration
rndc -p 54 reload

3. Forcing client cache flush
dscacheutil -flushcache

The reason I think this is better in my opinion is it gets rid of the potential “oops” of deleting critical files in /var/named.