Hi For several month the mail threading on this list broken and making the list hard to read. It can easily be seen by looking at the archive, in this link for about 9 mount(as of writing) https://lists.ceph.io/hyperkitty/list/ceph-users@ceph.io/latest?count=10&page=100 Subjects all have nice subject without "Re:" for replay, and on the right you see how may people(person icon) in the thread and number of post(talking bubble) in the thread. But if we look at more recent posts like this one https://lists.ceph.io/hyperkitty/list/ceph-users@ceph.io/latest?count=10&page=1 you see a lot of "Re:" in the subject and most of them have one person and only one post because the threading is broken. Take this recent mail "Weird behavior for 2 OSDs in our cluster" The fist mail by Wannes Smet https://lists.ceph.io/hyperkitty/list/ceph-users@ceph.io/thread/62B63BH33F3U... when i check my mail client this mail has following ID. "Message-ID: <0100019e7c77595f-ffb4d04b-1771-46cf-8b60-10795bc6a1c5-000000@email.amazonses.com>" The reply from Eugen Block https://lists.ceph.io/hyperkitty/list/ceph-users@ceph.io/thread/E63Z3JR7DMSS... the header says this is a reply to different ID "In-Reply-To: <0100019e7c7979e5-8d4d96e6-1c93-4a76-a5cd-efdf25ada853-000000@email.amazonses.com>" When I search the header of the mail from Wannes Smet I find no such ID that is in the In-Reply-To. It looks to me that the mailing-list server is sending different "Messages-ID" to the members on the list. This should be the same or the threading breaks as we can se. Can this be fixed please? -- Kai Stian Olstad