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Anand Buddhdev
Hi Martin. You are right. The DNS provisioning system also generates zonelets for address space registered in the RIPE Database, but whose reverse DNS zone is managed by another RIR. These zonelets are generated at 30 minutes past each hour, and published to the RIPE NCC's FTP server, in the directory /pub/zones, so that other RIRs can pick them up and insert the relevant records into their reverse zones. This is a slower process, and so it can take a few hours before such an "ERX delegation" appears in the relevant parent zone. During the outage, our provisioning system was not generating these zonelets, so the other RIRs had nothing to pick up (not even empty zonelets). Therefore, they made no changes in the zones they manage. As a result, the ERX delegations were still available. The slowness of the inter-RIR zonelet transfer process was a benefit in this case.