How Zone Files Are Read

[Reindl Harald]

Am 16.12.20 um 19:18 schrieb Tim Daneliuk:
> On 12/16/20 11:36 AM, Reindl Harald wrote:
>> where did i give the advice "don't fail"?
>> please read my repsonse again!
>>
>> * the zone fails on the master
>> * the zone is still available on the slaves
>> * so the error isn't fatal
>> * but you recognize your mistake
>>
>> what happens when the error is in the line of the MX record and named would say "well, it's only one line, we still have the zone but no longer an MX"?
>>
>> it would lead to a *fatal error* for the behavior of the whole zone, even if *all* or your nameservers go down it would be better because every delivering MTA would just queue the messages in case of a SERVFAIL
>>
>> without the MX the would go to the A record of the zone which is in most cases simply the wrong destination
> 
> I agree that in a master-slave topology, your argument makes sense

sorry, i can't think of any network with only one nameserver given that 
DNS is one of the most important services

> I this case, the server was a singleton responsible for a small virtual
> private network within a much larger one. So. when the server failed to start,
> the client had NO DNS for that subnet.
don't get me wrong but that's how one learns the hard way build basic 
redundancy for services he cares and if one don't care it's no problem 
if they fail

you have 3 options:

1: master/slave as recommended always
2: verify zones file before write them
3: fix software which generates broken zones

normally you chose all 3 in the sense of "and" instead of "or"