{
  "slug": "ceph-acting-set",
  "term": "Acting set (Ceph)",
  "aliases": [
    "Ceph acting set"
  ],
  "definition": "In Ceph, the acting set is the ordered OSD list responsible for a placement group at a particular map epoch.",
  "note": "It normally matches the up set but can be overridden through PG temp. Membership is not proof that every member has the latest contents. [ceph-peering]",
  "related": [
    "placement-group",
    "ceph-up-set",
    "ceph-peering"
  ],
  "citations": [
    {
      "id": "ceph-peering",
      "title": "Ceph Squid developer documentation: Peering, concepts",
      "url": "https://docs.ceph.com/en/squid/dev/peering/",
      "accessed": "2026-10-13"
    },
    {
      "id": "hesela-availability",
      "title": "Storage availability and correlated failures: placement boundaries",
      "url": "https://hesela.com/analyses/storage-availability-correlated-failures/",
      "accessed": "2026-10-13"
    }
  ],
  "status": "shipping",
  "advantages": [],
  "limitations": [],
  "supersedes": [],
  "supersededBy": [],
  "firstSeen": null,
  "lastSeen": null,
  "updated": "2026-10-13"
}