Using several Airport Extremes to create and extend corporate + guest wifi

Question

hello all,
my office has purchased 6 airport extremes for our new office, AirPort Extreme 802.11ac (6th Generation), running version 7.73
the plan was to hard wire one extreme via the wan port and create both a corporate and guest network
then link to the others throughout the office by wirelessly extending to provide complete coverage
after moving around the location of one or two units my coverage is now complete across the office space
my setup is as follows:
my network is a windows active directory setup where one of my domain controllers is my DHCP server in the range 192.168.x.x
to enable the guest network on my extremes i need to have my first hard wired (wan port) extreme unit configured in DHCP mode
this airport extreme has pulled down an ip address from my windows server in the range 192.168.x.x
the extreme then uses its own dhcp range to provide connectivity to my clients, 172.16.x.x for corporate wifi and 10.0.x.x for guest wifi
my issue is
the dhcp range that the extreme uses for all my corporate wifi users is 172.16.x.x
i cannot access any servers on my windows network 192.168.x.x by drive maps/hostnames as they are challenged for authentication
I can only access by using ip addresses instead of hostnames
all of my shares and wired users are configured to use hostnames for file shares, printers etc on my servers
the first extreme gets its DNS info from my windows dhcp server correctly but these settings are not passed down to my wifi clients
is there a way to do this ?
I have tried using the 'domain name' field on the extreme dhcp config but this had made no difference
can anyone advise on this ?
do i need to use a different setup, maybe switch to wired config ?
what i'd like to have is the following:
2 wireless networks, one for corporate users and one for guests/visitors
my corporate users to have access to all my corporate servers as their permissions allow using hostnames for access
my guest users to have internet access only
my 6 access points to be connected to each other either wired or wirelessly to provide coverage throughout my office
i was told that the 6 airport extreme's would allow me to do this but now i'm not so sure
any help or suggestions would be gratefully accepted,
thanks

Answer 1

You are trying to use Apple domestic products in a business setup.. this is not what they were designed for.
Could you use 3 units to cover the offices.. please have a go as this simplifies things tremendously.. just use three units in bridge.. preferably all connected to your ethernet network and so operating as AP only.
If that works then use the other 3 units for your guest network.. these should then be placed on a different vlan via your main managed switch.. so they can get internet but have no connection at all to the office network.. but other ways around it could be found. As you have already discovered a simple double NAT might sufficiently block guest access.