This is my environment:
2x V2110 EWCs - both configured as Availability Group.
Bridged at EWC Topology for Guest SSID - EWC1 = 192.168.44.5 and EWC2 = 192.168.44.6.
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To avoid SSL Certicate Error if the nonAuth Guest will be redirected to portal page (which reside on EWC) we use a public certificate.
This is a wildcard certificate to customers domain - let say *.example.com
So i have to redirect NOT to IP (which is default) i have redirect to FQDN portal.example.com
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Works fine if the DNS entry answers the IP of EWC1 =192.168.44.5.
But what about EWC redundancy and the 2 different IP in this EWC Topology ??
What happens if EWC1 fails and EWC2 which have IP 192.168.44.6 runs the portal - DNS answers 192.168.44.5 - so portal fails!
What is the solution ?
First idea was to configure portal1.example.com on EWC1 and portal2.example.com on EWC2 but the above screen was configured at WLAN Service level - so this will be at once replicated to other EWC - only one common value is configureable.
Second idea is to make two DNS Entries portal.example.com = 192.168.44.5, portal.example.com = 192.168.44.6.
But how does this work if both EWC are working. I fear this was not considered by design and will not work correctly.
But what is the best solution ?