[Apologies for duplicates] Dear Colleagues, At 13:50 on Thursday, 21 January, an error was introduced into the RIPE NCC's reverse DNS provisioning system. This caused reverse DNS delegations to stop working for allocations in the following range: 77.0.0.0 to 77.220.7.255 This error was triggered by an internal cleanup of our Early Registration Transfer (ERX) DNS delegations, which was being conducted as part of the RIPE NCC's Registration Data Quality (RDQ) project. The reverse DNS provisioning system was corrected again on 22 January at 09:50 (UTC). However, due to negative caching in DNS resolvers, the problem may have remained visible for a further two hours. The RIPE NCC is currently revising the reverse DNS provisioning system to prevent errors such as this occurring in future. If you have any questions or comments, please send an email to <ncc@ripe.net>. Regards, Sjoerd Oostdijck DNS Services Group, RIPE NCC