TechnitiumSoftware/DnsServer · error · InvalidOperationException

Old and new record types do not match.

Error message

Old and new record types do not match.

What it means

Thrown by PrimaryZone.UpdateRecord (default case) when oldRecord.Type != newRecord.Type. UpdateRecord only swaps the rdata of a single RR; it cannot change a record's type. This is a precondition check, surfaced as InvalidOperationException.

Source

Thrown at DnsServerCore/Dns/Zones/PrimaryZone.cs:2756

        }

        public override void UpdateRecord(DnsResourceRecord oldRecord, DnsResourceRecord newRecord)
        {
            switch (oldRecord.Type)
            {
                case DnsResourceRecordType.SOA:
                    throw new InvalidOperationException("Cannot update record: use SetRecords() for " + oldRecord.Type.ToString() + " record");

                case DnsResourceRecordType.DNSKEY:
                case DnsResourceRecordType.RRSIG:
                case DnsResourceRecordType.NSEC:
                case DnsResourceRecordType.NSEC3PARAM:
                case DnsResourceRecordType.NSEC3:
                    throw new InvalidOperationException("Cannot update DNSSEC records.");

                default:
                    if (oldRecord.Type != newRecord.Type)
                        throw new InvalidOperationException("Old and new record types do not match.");

                    if ((_dnssecStatus != AuthZoneDnssecStatus.Unsigned) && newRecord.GetAuthGenericRecordInfo().Disabled)
                        throw new DnsServerException("Cannot update record: disabling records in a signed zones is not supported.");

                    if (newRecord.OriginalTtlValue > GetZoneSoaExpire())
                        throw new DnsServerException("Cannot update record: TTL cannot be greater than SOA EXPIRE.");

                    if (!TryDeleteRecord(oldRecord.Type, oldRecord.RDATA, out DnsResourceRecord deletedRecord))
                        throw new DnsServerException("Cannot update record: the record does not exists to be updated.");

                    AddRecord(newRecord, out IReadOnlyList<DnsResourceRecord> addedRecords, out IReadOnlyList<DnsResourceRecord> deletedRecords);

                    List<DnsResourceRecord> allDeletedRecords = new List<DnsResourceRecord>(deletedRecords.Count + 1);
                    allDeletedRecords.Add(deletedRecord);
                    allDeletedRecords.AddRange(deletedRecords);

                    CommitAndIncrementSerial(allDeletedRecords, addedRecords);

View on GitHub (pinned to d0484b6c1e)

Solutions

1. Ensure newRecord is constructed with the same Type as oldRecord.
2. If the type really must change, do a Delete(oldType) + Add(newType) sequence instead.
3. Assert type equality before calling UpdateRecord in generic code.

Example fix

// before
zone.UpdateRecord(oldRecord, newRecord); // newRecord.Type differs

// after
if (oldRecord.Type != newRecord.Type)
{
    zone.DeleteRecord(oldRecord.Type, oldRecord.RDATA);
    zone.AddRecord(newRecord);
}
else
    zone.UpdateRecord(oldRecord, newRecord);

if (oldRecord.Type != newRecord.Type)
{
    zone.DeleteRecord(oldRecord.Type, oldRecord.RDATA);
    zone.AddRecord(newRecord);
}
else
    zone.UpdateRecord(oldRecord, newRecord);

static bool TypesMatch(DnsResourceRecord a, DnsResourceRecord b) => a.Type == b.Type;

null

When it happens

Trigger: Calling zone.UpdateRecord(oldRecord, newRecord) where the two records have different DnsResourceRecordType values.

Common situations: Editor code that builds newRecord from a form where the user changed the type field; copy-paste between update calls with mismatched type constants; refactoring rdata objects across types.

Related errors

• Cannot update record: TTL cannot be greater than SOA EXPIRE.
• Cannot update record: the record does not exists to be updat
• Cannot add record: TTL cannot be greater than SOA EXPIRE.
• Cannot update record: use SetRecords() for {type} record
• Cannot update DNSSEC records.

AI-assisted analysis of TechnitiumSoftware/DnsServer@d0484b6c1e (2026-08-13). Data as JSON: /api/errors/f7b46f9dd8aad3e0. Report an issue: GitHub.