Which two restrictions are in place with regards to configuring mDNS? (Choose two.)
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A. B. C. D. E.CD.
mDNS (multicast Domain Name System) is a protocol used for resolving hostnames to IP addresses within small networks. When configuring mDNS, there are certain restrictions that need to be considered. Two of these restrictions are:
B. mDNS cannot use UDP port 5353 as the destination port: This is because UDP port 5353 is already reserved for another protocol called LLMNR (Link-Local Multicast Name Resolution). LLMNR is similar to mDNS in that it resolves hostnames to IP addresses within small networks. However, unlike mDNS, LLMNR is a Microsoft proprietary protocol and is not widely supported.
C. mDNS is not supported on FlexConnect APs with a locally switched WLAN: FlexConnect is a feature on Cisco wireless controllers that allows remote APs to switch client data locally instead of tunneling all client traffic back to the controller. When using FlexConnect, mDNS is not supported on APs that are switched locally because multicast traffic is not forwarded over the CAPWAP tunnel to the controller. This means that mDNS service discovery will not work across VLANs in a FlexConnect environment.
The other options listed are not restrictions when configuring mDNS:
A. mDNS uses only UDP port 5436 as a destination port: This is incorrect as mDNS uses UDP port 5353 as its destination port by default. It is possible to configure mDNS to use other ports as well.
D. Controller software must be newer than 7.0.6+: This is not a restriction as mDNS is supported on Cisco wireless controllers running software version 7.0.6 and later.
E. mDNS is not supported over IPv6: This is also incorrect as mDNS is fully compatible with both IPv4 and IPv6 networks. However, some older devices or software may not support mDNS over IPv6.