Dear colleagues, Between 17:00 UTC yesterday and 10:00 UTC today, we had an issue that affected some reverse DNS delegations. The delegations in the RIPE Database where the parent zone is operated by ARIN were affected. RIPE NCC publishes zonelet files containing these delegations, and these are picked up by ARIN's DNS provisioning system periodically. At the end of these zonelet files is a summary of the counts of various types of DNS records. A bug in our code accidentally published these summaries with zero counts, and as a result, the ARIN DNS provisioning system appears to have removed the delegations. We have corrected this bug, and the zonelet files now contain the correct counts. They have been published on the RIPE NCC FTP server, and ARIN's DNS provisioning system has picked them up and reintroduced the delegations. We apologise for any inconvenience caused by this. This is the first time that such an issue has occurred with delegations that are exchanged by the zonelet mechanism, and we will try to engineer monitoring to prevent such an outage in the future. RIPE NCC's delegations in the following ARIN-operated zones were affected. The majority of the other delegations in these zones come from ARIN and the other registries, and were not affected. 104.in-addr.arpa. 107.in-addr.arpa. 128.in-addr.arpa. 129.in-addr.arpa. 130.in-addr.arpa. 131.in-addr.arpa. 132.in-addr.arpa. 134.in-addr.arpa. 135.in-addr.arpa. 136.in-addr.arpa. 137.in-addr.arpa. 138.in-addr.arpa. 139.in-addr.arpa. 13.in-addr.arpa. 140.in-addr.arpa. 143.in-addr.arpa. 144.in-addr.arpa. 146.in-addr.arpa. 147.in-addr.arpa. 148.in-addr.arpa. 149.in-addr.arpa. 152.in-addr.arpa. 156.in-addr.arpa. 157.in-addr.arpa. 158.in-addr.arpa. 159.in-addr.arpa. 160.in-addr.arpa. 161.in-addr.arpa. 164.in-addr.arpa. 165.in-addr.arpa. 166.in-addr.arpa. 168.in-addr.arpa. 169.in-addr.arpa. 170.in-addr.arpa. 173.in-addr.arpa. 198.in-addr.arpa. 199.in-addr.arpa. 206.in-addr.arpa. 209.in-addr.arpa. 216.in-addr.arpa. 23.in-addr.arpa. 24.in-addr.arpa. 45.in-addr.arpa. 52.in-addr.arpa. 65.in-addr.arpa. 66.in-addr.arpa. Regards, Anand Buddhdev RIPE NCC