Ceph » rgw

# radosgw-admin metadata get bucket:slim
{
    "key": "bucket:slim",
    "ver": {
        "tag": "_M3XT0TRU1x93OpWQRQ81BO2",
        "ver": 1
    },
    "mtime": "2013-12-18 05:45:02.000000Z",
    "data": {
        "bucket": {
            "name": "slim",
            "marker": "default.42527465.160",
            "bucket_id": "default.42527465.160",
            "tenant": "",
            "explicit_placement": {
                "data_pool": ".rgw.data.1",
                "data_extra_pool": "",
                "index_pool": ".rgw.data.1" 
            }
        },
        "owner": "coderpetebackups",
        "creation_time": "2013-12-18 05:44:27.000000Z",
        "linked": "true",
        "has_bucket_info": "false" 
    }
}

# radosgw-admin metadata get bucket.instance:slim:default.42527465.160
{
    "key": "bucket.instance:slim:default.42527465.160",
    "ver": {
        "tag": "_8nmhy2zl-eiLg3WQb0yUSCR",
        "ver": 1
    },
    "mtime": "2013-12-18 05:44:27.000000Z",
    "data": {
        "bucket_info": {
            "bucket": {
                "name": "slim",
                "marker": "default.42527465.160",
                "bucket_id": "default.42527465.160",
                "tenant": "",
                "explicit_placement": {
                    "data_pool": ".rgw.data.1",
                    "data_extra_pool": "",
                    "index_pool": ".rgw.data.1" 
                }
            },
            "creation_time": "2013-12-18 05:44:27.000000Z",
            "owner": "coderpetebackups",
            "flags": 0,
            "zonegroup": "default",
            "placement_rule": "",
            "has_instance_obj": "true",
            "quota": {
                "enabled": false,
                "check_on_raw": false,
                "max_size": -1,
                "max_size_kb": 0,
                "max_objects": -1
            },
            "num_shards": 0,
            "bi_shard_hash_type": 0,
            "requester_pays": "false",
            "has_website": "false",
            "swift_versioning": "false",
            "swift_ver_location": "",
            "index_type": 0,
            "mdsearch_config": [],
            "reshard_status": 0,
            "new_bucket_instance_id": "" 
        },
        "attrs": [
            {
                "key": "user.rgw.acl",
                "val": "AgK7AAAAAgIoAAAAEAAAAGNvZGVycGV0ZWJhY2t1cHMQAAAAY29kZXJwZXRlYmFja3VwcwMDhwAAAAEBAAAAEAAAAGNvZGVycGV0ZWJhY2t1cHMPAAAAAQAAABAAAABjb2RlcnBldGViYWNrdXBzAwNIAAAAAgIEAAAAAAAAABAAAABjb2RlcnBldGViYWNrdXBzAAAAAAAAAAACAgQAAAAPAAAAEAAAAGNvZGVycGV0ZWJhY2t1cHMAAAAAAAAAAA==" 
            },
            {
                "key": "user.rgw.idtag",
                "val": "" 
            }
        ]
    }
}

# radosgw-admin --bucket slim bi list
[]

# radosgw-admin --bucket slim bucket stats
{
    "bucket": "slim",
    "zonegroup": "",
    "placement_rule": "",
    "explicit_placement": {
        "data_pool": ".rgw.data.1",
        "data_extra_pool": "",
        "index_pool": ".rgw.data.1" 
    },
    "id": "default.42527465.160",
    "marker": "default.42527465.160",
    "index_type": "Normal",
    "owner": "coderpetebackups",
    "ver": "0#0",
    "master_ver": "0#0",
    "mtime": "0.000000",
    "max_marker": "0#",
    "usage": {},
    "bucket_quota": {
        "enabled": false,
        "check_on_raw": false,
        "max_size": -1,
        "max_size_kb": 0,
        "max_objects": -1
    }
}

# radosgw-admin --bucket slim bucket reshard --num-shards=1 --yes-i-really-mean-it
*** NOTICE: operation will not remove old bucket index objects ***
***         these will need to be removed manually             ***
tenant: 
bucket name: slim
old bucket instance id: default.42527465.160
new bucket instance id: default.497541194.1
total entries: 1000 2000 3000 4000 5000 6000 7000 7544

# radosgw-admin --bucket slim bucket stats
{
    "bucket": "slim",
    "zonegroup": "default",
    "placement_rule": "",
    "explicit_placement": {
        "data_pool": ".rgw.data.1",
        "data_extra_pool": "",
        "index_pool": ".rgw.data.1" 
    },
    "id": "default.497541194.1",
    "marker": "default.42527465.160",
    "index_type": "Normal",
    "owner": "coderpetebackups",
    "ver": "0#119",
    "master_ver": "0#0",
    "mtime": "2018-01-23 00:42:50.472315",
    "max_marker": "0#",
    "usage": {
        "rgw.main": {
            "size": 198745513198,
            "size_actual": 198760845312,
            "size_utilized": 0,
            "size_kb": 194087416,
            "size_kb_actual": 194102388,
            "size_kb_utilized": 0,
            "num_objects": 7544
        }
    },
    "bucket_quota": {
        "enabled": false,
        "check_on_raw": false,
        "max_size": -1,
        "max_size_kb": 0,
        "max_objects": -1
    }
}

# radosgw-admin --bucket slim bi list
[
    {
        "type": "plain",
        "idx": "REDACTED-FILENAME",
        "entry": {
            "name": "REDACTED-FILENAME",
            "instance": "",
            "ver": {
                "pool": 5,
                "epoch": 23248
            },
            "locator": "REDACTED-FILENAME",
            "exists": "true",
            "meta": {
                "category": 1,
                "size": 149535251,
                "mtime": "2014-01-16 10:29:20.000000Z",
                "etag": "dfe750683dd66f67b163baa5344361b4",
                "owner": "coderpetebackups",
                "owner_display_name": "coderpetebackups",
                "content_type": "application/octet-stream",
                "accounted_size": 149535251,
                "user_data": "" 
            },
            "tag": "default.45239442.2806223",
            "flags": 0,
            "pending_map": [],
            "versioned_epoch": 0
        }
    },
    ...

As shown, resharding the bucket will make the content show up again; but you have to know that it is missing first. offline reshard also presently breaks ACLs, but there is a fix in flight for that.

The bug is actually in rados. The problem is that the omap flag was never set on the index objects due to an old rados bug, and now there's an optimization that returns empty result when fetching omap entries if the omap flag is not set on the object. The workaround sets that flag.

Just to be clear, note the workaround in comment #3.