SOA values
(2019-09-11)
I've only been doing this for 25 years, I guess it's high time I learned what it all means
[root@n2 log]# dig +short soa xdroop.com
n1.gridway.net. info.gridway.net. 2019050703 86400 3600 604800 7200
| The numeric values are: SOA Value | Name | Description |
|---|---|---|
| 2019050703 | Zone serial number | Nameserver will not use new versions of this zone if the presented serial number is less than the currently used value. |
| 86400 | Refresh | Slave nameservers will try to pull an updated copy of the zone from the master every <Refresh> seconds. |
| 3600 | Retry | If a slave's transaction with a master fails for some reason, the slave will try again in <Retry> seconds. |
| 604800 | Expire | The maximum amount of time that a slave will keep a zone cached if it can't talk to the master. |
| 7200 | TTL | This is the amount of time that negative answers are to be cached on downstream nameservers. Needs to be lower for zones that need to propagate quickly. |