Introduction
Glue record misconfiguration can break an entire domain before resolvers even reach the authoritative zone. This happens most often when a domain uses custom nameservers under its own hostname, and the registrar still points those hosts to outdated IP addresses. The fix is to treat glue as registrar-level infrastructure, not as an ordinary zone record you can update in only one place.
Symptoms
- The domain fails to resolve after changing nameserver IPs or moving DNS servers
- Some resolvers hit old nameserver addresses while others eventually recover
- DNS checks flag broken or inconsistent glue for in-bailiwick nameservers
- The zone itself looks correct, but resolvers cannot reliably reach the authoritative servers
- The issue began after server migration, failover, or registrar-side changes
Common Causes
- Registrar host records still point to old nameserver IP addresses
- Only the zone's A records were updated, leaving registrar glue unchanged
- Multiple custom nameservers were updated inconsistently during migration
- Old server IPs still answer partially, making the failure intermittent and harder to spot
- Delegation and authoritative DNS changes were made in the wrong order during cutover
Step-by-Step Fix
- Confirm whether the domain uses in-bailiwick nameservers such as
ns1.yourdomain.comthat require glue records. - Check the registrar host-record configuration and compare each glue IP with the actual live nameserver addresses.
- Verify the nameserver hosts themselves resolve consistently and answer authoritatively for the zone.
- Update registrar glue records where needed, not just DNS zone A records inside the domain.
- Remove obsolete nameserver IPs from the migration path so resolvers do not continue reaching dead infrastructure.
- Query the parent delegation and authoritative servers separately to confirm the correction is visible at both levels.
- Test resolution for the domain and subdomains from external resolvers after the glue change propagates.
- Validate related services such as website traffic, mail routing, and verification records once delegation is healthy.
- Keep nameserver migration runbooks explicit about glue dependencies so future cutovers do not leave parent and child data out of sync.