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Mismatch between "prefix-length" and "preference" in dhcp6-server syntax
Closed, ResolvedPublicBUG


In the context:

service dhcpv6-server shared-network-name <text> subnet <h:h:h:h:h:h:h:h/x> prefix-delegation  start <h:h:h:h:h:h:h:h> prefix-length

The prefix-length context help and value validator incorrectly assumes we are entering "preference" configuration with valid range between 0 and 255.

So it might have been mixed with this configuration syntax during validation and for context help lookup:

service dhcpv6-server preference

The attached image evaluates different boundary values including the incorrect ones such as 129, 255, etc that are accepted by the syntax validator. When exceeding 255, a help message is printed suggesting the values between 0 and 255 which is not applicable to prefix-length.


Difficulty level
Easy (less than an hour)
Why the issue appeared?
Implementation mistake
Is it a breaking change?
Perfectly compatible
Issue type
Improvement (missing useful functionality)

Event Timeline

c-po claimed this task.
c-po triaged this task as Low priority.
c-po changed Difficulty level from Unknown (require assessment) to Easy (less than an hour).
c-po changed Why the issue appeared? from Will be filled on close to Implementation mistake.
c-po changed Is it a breaking change? from Unspecified (possibly destroys the router) to Perfectly compatible.
erkin set Issue type to Improvement (missing useful functionality).Aug 29 2021, 12:31 PM
erkin removed a subscriber: Active contributors.