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Mario_Franco's avatar
Mario_Franco
Icon for Altocumulus rankAltocumulus
2 years ago

Implementing F5 DNS and Creating Custom CNAME Redirects

We are currently implementing a solution in Azure and have encountered some DNS-related issues. I think it's a good idea to implement F5 DNS. However, I wonder if we can create an iRule to set up a C...
application delivery
DNS
irules
VishnuGatla's avatar
VishnuGatla
Icon for Cumulonimbus rankCumulonimbus
2 years ago

Your approach to use an iRule on F5 DNS to manipulate DNS requests and responses is correct. However, the issue you're facing might be due to how DNS resolution works and the context in which iRules operate. The iRule you provided is designed to modify the DNS request for "example.com" to "example.2.com", and then create a CNAME record in the DNS response. When you perform a DNS lookup for "example.com", the lookup is redirected to "example.2.com". However, this does not necessarily mean that "example.2.com" will resolve correctly.

  • Mario_Franco's avatar
    Mario_Franco
    Icon for Altocumulus rankAltocumulus
    2 years ago

    If I try to consume test.example.2.com it works, however, when I verify the nslookup output for test.example.com it doesn't show the cname or even an answer, it's just empty, however verifying the logs the irule is creating the cname record but looks like it's not returning the answer to the client