Wow that was a long title, but just what I have been dealing with recently. The first solution which, is easy, is to use Kerberos, this works great unless you also want authenticationto fall back to a standard.htpasswd` file. In that case you need to use LDAP. Why? because LDAP and File use the same AuthType of Basic where as Kerberos uses an AuthType of Kerberos. Using LDAP and File authentication you can use a config like this

<Directory /var/www/html/private>
    SSLRequireSSL
    AuthName "Private"
    AuthType Basic
    AuthBasicProvider ldap file

    # File Auth
    AuthUserFile /var/www/.htpasswd

    AuthLDAPURL "ldap://ADServer.domain.co.uk/ou=Users,dc=domain,dc=co,dc=uk?sAMAccountName?sub?(objectClass=*)"
    AuthLDAPBindDN User@Domain.co.uk
    AuthLDAPBindPassword XXXXXXX

    AuthzLDAPAuthoritative off
    Require valid-user
    Satisfy any
</Directory>

This works unless you have your users split over a number of OUs in the Active Directory. If that is the case here is the way I got around it.

<AuthnProviderAlias ldap ldap-group1>
    AuthLDAPURL "ldap://ADServer.domain.co.uk/ou=Group-OU1,dc=domain,dc=co,dc=uk?sAMAccountName?sub?(objectClass=*)"
    AuthLDAPBindDN User@Domain.co.uk
    AuthLDAPBindPassword XXXXXXX
</AuthnProviderAlias>

<AuthnProviderAlias ldap ldap-group2>
    AuthLDAPURL "ldap://ADServer.domain.co.uk/ou=Group-OU2,dc=domain,dc=co,dc=uk?sAMAccountName?sub?(objectClass=*)"
    AuthLDAPBindDN User@Domain.co.uk
    AuthLDAPBindPassword XXXXXXX
</AuthnProviderAlias>

<Directory /var/www/html/private>
    SSLRequireSSL
    AuthName "Private"
    AuthType Basic
    AuthBasicProvider ldap-group1 ldap-group2 file

    # File Auth
    AuthUserFile /var/www/.htpasswd

    AuthzLDAPAuthoritative off
    Require valid-user
    Satisfy any
</Directory>

Well I have just figured out why some of the machines that I use had stopped picking up updates. When I look at the list of systems on the RedHat Network they had a list of updates that they hadn’t picked up but when I logged into the machines and ran

yum update

it said there were no updates. After trying a lot of things on one of the systems that I was free to test with I still couldn’t find out what was going on. Eventually I discovered that yum had corrupted it’s cache and so it thought that its list of packages was up to date when it wasn’t. The solution was quite easy after that

yum clean all

yum update

I know, I should have tried that at the start.