Solution #00005481
Scope:
All Barracuda Link Balancer models, firmware version 2.1 and above.
Answer:
Per RFC: 1034:
You can't have a CNAME at the same point as other DNS records.
"Section 3.6.2 of RFC 1034:
A CNAME RR identifies its owner name as an alias, and specifies the corresponding canonical name in the RDATA section of the RR (Resource Record). If a CNAME RR is present at a node, no other data should be present; this ensures that the data for a canonical name and its aliases cannot be different. This rule also insures that a cached CNAME can be used without checking with an authoritative server for other RR types."
Example of What is NOT Allowed in a Zone File:
States zzz.com resolves to the 'A Record IP 74.76.78.254 ' used by abc.com and '@' A record '84.86.88.254'.
DNS Server A zone file - zzz.com
@ 10 IN CNAME abc.com.
@ 10 IN A 84.86.88.254
DNS Server B: zone file - abc.com
abc.com. 1630 IN A 74.76.78.254
Example of What IS Allowed in a Zone File:
States bob.zzz.com can be found at 'abc.com's 'A Record IP 74.76.78.254' and 'zzz.com' resolves to '@' A Record 84.86.88.254
DNS Server A zone file - zzz.com
bob 10 IN CNAME abc.com.
@ 10 IN A 84.86.88.254
DNS Server B: zone file - abc.com
abc.com. 1630 IN A 74.76.78.254
Link to this page:States zzz.com resolves to the 'A Record IP 74.76.78.254 ' used by abc.com and '@' A record '84.86.88.254'.
DNS Server A zone file - zzz.com
@ 10 IN CNAME abc.com.
@ 10 IN A 84.86.88.254
DNS Server B: zone file - abc.com
abc.com. 1630 IN A 74.76.78.254
Example of What IS Allowed in a Zone File:
States bob.zzz.com can be found at 'abc.com's 'A Record IP 74.76.78.254' and 'zzz.com' resolves to '@' A Record 84.86.88.254
DNS Server A zone file - zzz.com
bob 10 IN CNAME abc.com.
@ 10 IN A 84.86.88.254
DNS Server B: zone file - abc.com
abc.com. 1630 IN A 74.76.78.254
https://campus.barracuda.com/solution/50160000000IQlOAAW