Zone serial numbers are just numbers-they aren't date +
Zone serial numbers are just numbers — they aren't date related. A lot of people set them to a number that represents a - date, usually of the form YYYYMMDDRR. A number of people have been - testing these numbers for Y2K compliance and have set the number - to the year 2000 to see if it will work. They then try to restore - the old serial number. This will cause problems because serial + date, usually of the form YYYYMMDDRR. A number of people + tested these numbers for Y2K compliance and set the number + to the year 2000 to see if it would work. They then tried to restore + the old serial number. This caused problems because serial numbers are used to indicate that a zone has been updated. If the serial number on the slave server is lower than the serial number on the master, the slave server will attempt to update its copy of