debmirror, version 1:2.25ubuntu2, on my xenial server seems to have stopped mirroring Contents-amd64.gz and Contents-i386.gz for trusty's release pocket. I believe this is a recent development.
$ find /mnt/storage/archive-mirror/dists/ -name Contents-amd64.gz | sort
/mnt/storage/archive-mirror/dists/trusty-backports/Contents-amd64.gz
/mnt/storage/archive-mirror/dists/trusty-proposed/Contents-amd64.gz
/mnt/storage/archive-mirror/dists/trusty-security/Contents-amd64.gz
/mnt/storage/archive-mirror/dists/trusty-updates/Contents-amd64.gz
/mnt/storage/archive-mirror/dists/xenial-backports/Contents-amd64.gz
/mnt/storage/archive-mirror/dists/xenial/Contents-amd64.gz
/mnt/storage/archive-mirror/dists/xenial-proposed/Contents-amd64.gz
/mnt/storage/archive-mirror/dists/xenial-security/Contents-amd64.gz
/mnt/storage/archive-mirror/dists/xenial-updates/Contents-amd64.gz
/mnt/storage/archive-mirror/dists/yakkety-backports/Contents-amd64.gz
/mnt/storage/archive-mirror/dists/yakkety/Contents-amd64.gz
/mnt/storage/archive-mirror/dists/yakkety-proposed/Contents-amd64.gz
/mnt/storage/archive-mirror/dists/yakkety-security/Contents-amd64.gz
/mnt/storage/archive-mirror/dists/yakkety-updates/Contents-amd64.gz
/mnt/storage/archive-mirror/dists/zesty-backports/Contents-amd64.gz
/mnt/storage/archive-mirror/dists/zesty/Contents-amd64.gz
/mnt/storage/archive-mirror/dists/zesty-proposed/Contents-amd64.gz
/mnt/storage/archive-mirror/dists/zesty-security/Contents-amd64.gz
/mnt/storage/archive-mirror/dists/zesty-updates/Contents-amd64.gz
Strangely, every other contents file is there. I've switched mirrors and trusty's didn't appear after rerunning debmirror. This is the command I'm using:
debmirror --progress --method http --host mirrors.accretive-networks.net --dist trusty,trusty-proposed,trusty-updates,trusty-security,trusty-backports,xenial,xenial-proposed,xenial-updates,xenial-backports,xenial-security,yakkety,yakkety-proposed,yakkety-updates,yakkety-backports,yakkety-security,zesty,zesty-proposed,zesty-updates,zesty-backports,zesty-security --section main,universe,multiverse,restricted --arch amd64,i386 --getcontents /mnt/storage/archive-mirror
I tried using diff=none and that didn't help.