============= RGW Multisite ============= .. versionadded:: Jewel From Ceph release Jewel and beyond, you may configure each :term:`Ceph Object Gateway` to work in an active active zone configuration, allowing for writing to non-master zones. Following are the basic terminologies that would be used: - **Zone**: A zone is *logical* grouping of one or more Ceph Object Gateway instances. There will be one zone that should be designated as the master zone in a zonegroup, which will handle all bucket and user creation. - **Zonegroup**: A zonegroup consists of multiple zones, this approximately corresponds to what used to be called as a region in pre Jewel releases for federated deployments. There should be a master zonegroup that will handle changes to the system configuration. - **Zonegroup map**: A zonegroup map is a configuration structure that holds the map of the entire system, ie. which zonegroup is the master, relationships between different zonegroups and certain configurables like storage policies. - **Realm**: A realm is a container for zonegroups, this allows for separation of zonegroups themselves between clusters. It is possible to create multiple realms, making it easier to run completely different configurations in the same cluster. - **Period**: A period holds the configuration structure for the current state of the realm. Every period contains a unique id and an epoch. A period's epoch is incremented on every commit operation. Every realm has an associated current period, holding the current state of configuration of the zonegroups and storage policies. Any configuration change for a non-master zone will increment the period's epoch. Changing the master zone to a different zone will trigger the following changes: - A new period is generated with a new period id and epoch of 1 - Realm's current period is updated to point to the newly generated period id - Realm's epoch is incremented About this guide ================ In this guide we use 2 Ceph clusters, and create a single zonegroup, with three zones, which sync data between them actively. For the purpose of the guide, we'll create 2 zones in the same cluster, and 1 zone in a different cluster. There is no sync agent involved for mirroring data changes between the Ceph Object Gateway instances and this allows for a much simpler configuration scheme and active-active configurations. Please note that metadata operations such as creating a user would still need to go through the master zone, however data operations such as creation of buckets objects can be handled by any of the zones. System Keys ----------- While configuring zones, Ceph Object Gateway instance, expects creation of zone a system user, with a S3-like access and secret keys. This allows another Ceph Object Gateway instance to pull the configuration remotely, with the access and secret keys. For making scripting and using of configuration management tools easier, it would be easier to generate the access key and secret key before hand and use these. For the purpose of the guide we assume an access key and secret key are set in the environment. For eg.:: $ SYSTEM_ACCESS_KEY=1555b35654ad1656d805 $ SYSTEM_SECRET_KEY=h7GhxuBLTrlhVUyxSPUKUV8r/2EI4ngqJxD7iBdBYLhwluN30JaT3Q12 Generally access keys are 20 alphanumeric characters, secret keys are 40 alphanumeric characters (they can contain +/= chars as well). These keys can be generated in shell for eg:: $ SYSTEM_ACCESS_KEY=$(cat /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 20 | head -n 1) $ SYSTEM_SECRET_KEY=$(cat /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 40 | head -n 1) Then we can create a system user by following command:: $ radosgw-admin user create --uid=zone.user --display-name="Zone User" \ --access-key=$SYSTEM_ACCESS_KEY --secret=$SYSTEM_SECRET_KEY --system Naming conventions ------------------ This section describes the process of setting up a master zone. For the purpose of the guide, we'll assume a zonegroup called ``us`` spanning the United States, which will be our master zonegroup. This will contain two zones written in a ``{zonegroup}-{zone}`` format, this is just a convention only and you are free to choose a format you prefer to set these names. So in summary: - Master Zonegroup: United States ``us`` - Master zone: United States, East Region 1: ``us-east-1`` - Second zone: United States, East Region 2: ``us-east-2`` - Second zone: United States, West Region: ``us-west`` This will be a part of a larger realm, say ``gold``. The zones ``us-east-1`` and ``us-east-2`` are part of the same Ceph cluster, of which we'll make ``us-east-1`` as the primary. ``us-west`` will be in a different Ceph cluster. Create Pools ------------ Ceph Object Gateway instance will create pools on its own, when it is configured with the appropriate permissions, this will be done with the value of ``pg_num`` and ``pgp_num`` from the ``ceph.conf``. See `Ceph Object Gateway - Create Pools`_ for more detailed explanation. Pools particular to a zone by default follows the convention of ``{zone-name}.pool-name``. In the default configuration, for eg. in ``us-east-1`` zone following will be the pools: - ``.rgw.root`` - ``us-east-1.rgw.control`` - ``us-east-1.rgw.data.root`` - ``us-east-1.rgw.gc`` - ``us-east-1.rgw.log`` - ``us-east-1.rgw.intent-log`` - ``us-east-1.rgw.usage`` - ``us-east-1.rgw.users.keys`` - ``us-east-1.rgw.users.email`` - ``us-east-1.rgw.users.swift`` - ``us-east-1.rgw.users.uid`` - ``us-east-1.rgw.buckets.index`` - ``us-east-1.rgw.buckets.data`` - ``us-east-1.rgw.meta`` These pools can be created in the other zones as well by replacing ``us-east-1`` with the appropriate zone name. Configuring the master zone in the primary cluster ================================================== First, we'll configure the master zone ``us-east-1``, in the master zonegroup ``us``, this will serve as the master zone for all metadata operations, so all operations like creation of users need to be done on this zone. Creating a realm ---------------- Configure a realm called ``gold``, and also make this as default :: # radosgw-admin realm create --rgw-realm=gold --default { "id": "4a367026-bd8f-40ee-b486-8212482ddcd7", "name": "gold", "current_period": "09559832-67a4-4101-8b3f-10dfcd6b2707", "epoch": 1 } Note that every realm has an id, which allows for flexibility like renaming the realm later, should the need arise. The ``current_period`` changes whenever we change anything in the master zone. The ``epoch`` is incremented when there's a change in configuration of the master zone, which results in a change of current period. Deleting the default zonegroup ------------------------------ A simple installation of Ceph Object Gateway would assume the default zonegroup called "default", since we no longer need this we begin by removing the default zonegroup:: # radosgw-admin zonegroup delete --rgw-zonegroup=default Creating a master zonegroup --------------------------- We'll create a zonegroup called ``us`` as master zonegroup. A master zonegroup will be in control of the zonegroup map and propagate changes to the rest of the system. We will also set this zonegroup as the default, which allows later commands to use this zonegroup without explicitly mentioning it with the ``--rgw-zonegroup`` option. :: # radosgw-admin zonegroup create --rgw-zonegroup=us --endpoints=http://rgw1:80 --master --default { "id": "d4018b8d-8c0d-4072-8919-608726fa369e", "name": "us", "api_name": "us", "is_master": "true", "endpoints": [ "http:\/\/rgw1:80" ], "hostnames": [], "hostnames_s3website": [], "master_zone": "", "zones": [], "placement_targets": [], "default_placement": "", "realm_id": "4a367026-bd8f-40ee-b486-8212482ddcd7" } Alternatively, we can make this zonegroup as the default zonegroup via the following command :: # radosgw-admin zonegroup default --rgw-zonegroup=us Creating a master zone ---------------------- Next we create a zone, and make it as the default zone. Note that for metadata operations like user creation you would want to use this zone. We also add it to the zonegroup :: # radosgw-admin zone create --rgw-zonegroup=us --rgw-zone=us-east-1 --endpoints=http://rgw1:80 --access-key=$SYSTEM_ACCESS_KEY --secret=$SYSTEM_SECRET_KEY --default --master { "id": "83859a9a-9901-4f00-aa6d-285c777e10f0", "name": "us-east-1", "domain_root": "us-east-1.rgw.data.root", "control_pool": "us-east-1.rgw.control", "gc_pool": "us-east-1.rgw.gc", "log_pool": "us-east-1.rgw.log", "intent_log_pool": "us-east-1.rgw.intent-log", "usage_log_pool": "us-east-1.rgw.usage", "user_keys_pool": "us-east-1.rgw.users.keys", "user_email_pool": "us-east-1.rgw.users.email", "user_swift_pool": "us-east-1.rgw.users.swift", "user_uid_pool": "us-east-1.rgw.users.uid", "system_key": { "access_key": "1555b35654ad1656d804", "secret_key": "h7GhxuBLTrlhVUyxSPUKUV8r\/2EI4ngqJxD7iBdBYLhwluN30JaT3Q==" }, "placement_pools": [ { "key": "default-placement", "val": { "index_pool": "us-east-1.rgw.buckets.index", "data_pool": "us-east-1.rgw.buckets.data", "data_extra_pool": "us-east-1.rgw.buckets.non-ec", "index_type": 0 } } ], "metadata_heap": "us-east-1.rgw.meta", "realm_id": "4a367026-bd8f-40ee-b486-8212482ddcd7" } Note that the above ``--rgw-zonegroup`` and ``--default`` options add the zone to a zonegroup and makes it the default zone as well. This can also be accomplished by the following commands:: # radosgw-admin zone default --rgw-zone=us-east-1 # radosgw-admin zonegroup add --rgw-zonegroup=us --rgw-zone=us-east-1 Creating system users --------------------- Next we create the system users for accessing the zone pools, note that these keys would be used when configuring the second zone:: # radosgw-admin user create --uid=zone.user --display-name="Zone User" --access-key=$SYSTEM_ACCESS_KEY --secret=$SYSTEM_SECRET_KEY --system { "user_id": "zone.user", "display_name": "Zone User", "email": "", "suspended": 0, "max_buckets": 1000, "auid": 0, "subusers": [], "keys": [ { "user": "zone.user", "access_key": "1555b35654ad1656d804", "secret_key": "h7GhxuBLTrlhVUyxSPUKUV8r\/2EI4ngqJxD7iBdBYLhwluN30JaT3Q==" } ], "swift_keys": [], "caps": [], "op_mask": "read, write, delete", "system": "true", "default_placement": "", "placement_tags": [], "bucket_quota": { "enabled": false, "max_size_kb": -1, "max_objects": -1 }, "user_quota": { "enabled": false, "max_size_kb": -1, "max_objects": -1 }, "temp_url_keys": [] } Update the period ----------------- Since we have made a change in the master zone configuration, we need to commit these zone changes to reflect in the realm configuration structure. This is what the period would look like initially:: # radosgw-admin period get { "id": "09559832-67a4-4101-8b3f-10dfcd6b2707", "epoch": 1, "predecessor_uuid": "", "sync_status": [], "period_map": { "id": "09559832-67a4-4101-8b3f-10dfcd6b2707", "zonegroups": [], "short_zone_ids": [] }, "master_zonegroup": "", "master_zone": "", "period_config": { "bucket_quota": { "enabled": false, "max_size_kb": -1, "max_objects": -1 }, "user_quota": { "enabled": false, "max_size_kb": -1, "max_objects": -1 } }, "realm_id": "4a367026-bd8f-40ee-b486-8212482ddcd7", "realm_name": "gold", "realm_epoch": 1 } Now we update the period and commit the changes:: # radosgw-admin period update --commit { "id": "b5e4d3ec-2a62-4746-b479-4b2bc14b27d1", "epoch": 1, "predecessor_uuid": "09559832-67a4-4101-8b3f-10dfcd6b2707", "sync_status": [ ""... # truncating the output here ], "period_map": { "id": "b5e4d3ec-2a62-4746-b479-4b2bc14b27d1", "zonegroups": [ { "id": "d4018b8d-8c0d-4072-8919-608726fa369e", "name": "us", "api_name": "us", "is_master": "true", "endpoints": [ "http:\/\/rgw1:80" ], "hostnames": [], "hostnames_s3website": [], "master_zone": "83859a9a-9901-4f00-aa6d-285c777e10f0", "zones": [ { "id": "83859a9a-9901-4f00-aa6d-285c777e10f0", "name": "us-east-1", "endpoints": [ "http:\/\/rgw1:80" ], "log_meta": "true", "log_data": "false", "bucket_index_max_shards": 0, "read_only": "false" } ], "placement_targets": [ { "name": "default-placement", "tags": [] } ], "default_placement": "default-placement", "realm_id": "4a367026-bd8f-40ee-b486-8212482ddcd7" } ], "short_zone_ids": [ { "key": "83859a9a-9901-4f00-aa6d-285c777e10f0", "val": 630926044 } ] }, "master_zonegroup": "d4018b8d-8c0d-4072-8919-608726fa369e", "master_zone": "83859a9a-9901-4f00-aa6d-285c777e10f0", "period_config": { "bucket_quota": { "enabled": false, "max_size_kb": -1, "max_objects": -1 }, "user_quota": { "enabled": false, "max_size_kb": -1, "max_objects": -1 } }, "realm_id": "4a367026-bd8f-40ee-b486-8212482ddcd7", "realm_name": "gold", "realm_epoch": 2 } Starting the Ceph Object Gateway instance ----------------------------------------- Before starting the Ceph Object Gateway instance, the ``rgw_zone`` and ``rgw_frontends`` options need to be mentioned in the configuration file. For more details refer to the `Install Ceph Gateway`_ section of the guide. The configuration section for Ceph Object Gateway instance should resemble:: [client.rgw.us-east-1] rgw_frontends="civetweb port=80" rgw_zone=us-east-1 And start the Ceph Object Gateway instance(according to the OS installation) :: $ sudo systemctl start ceph-radosgw@rgw.us-east-1 Configuring the second zone in same cluster =========================================== Now we configure the second zone, ``us-east-2``, in the same cluster. For the same cluster, all the following commands can be executed in the node hosting the primary zone itself. Creating the second zone ------------------------ We follow a similar step to creation of master zone, except dropping the ``--master`` flag this time :: # radosgw-admin zone create --rgw-zonegroup=us --rgw-zone=us-east-2 --access-key=$SYSTEM_ACCESS_KEY --secret=$SYSTEM_SECRET_KEY --endpoints=http://rgw2:80 { "id": "950c1a43-6836-41a2-a161-64777e07e8b8", "name": "us-east-2", "domain_root": "us-east-2.rgw.data.root", "control_pool": "us-east-2.rgw.control", "gc_pool": "us-east-2.rgw.gc", "log_pool": "us-east-2.rgw.log", "intent_log_pool": "us-east-2.rgw.intent-log", "usage_log_pool": "us-east-2.rgw.usage", "user_keys_pool": "us-east-2.rgw.users.keys", "user_email_pool": "us-east-2.rgw.users.email", "user_swift_pool": "us-east-2.rgw.users.swift", "user_uid_pool": "us-east-2.rgw.users.uid", "system_key": { "access_key": "1555b35654ad1656d804", "secret_key": "h7GhxuBLTrlhVUyxSPUKUV8r\/2EI4ngqJxD7iBdBYLhwluN30JaT3Q==" }, "placement_pools": [ { "key": "default-placement", "val": { "index_pool": "us-east-2.rgw.buckets.index", "data_pool": "us-east-2.rgw.buckets.data", "data_extra_pool": "us-east-2.rgw.buckets.non-ec", "index_type": 0 } } ], "metadata_heap": "us-east-2.rgw.meta", "realm_id": "815d74c2-80d6-4e63-8cfc-232037f7ff5c" } Updating the period ------------------- Next we inform all the Ceph Object Gateway instances of the new change in the system map by doing a period update and committing the changes:: # radosgw-admin period update --commit { "id": "b5e4d3ec-2a62-4746-b479-4b2bc14b27d1", "epoch": 2, "predecessor_uuid": "09559832-67a4-4101-8b3f-10dfcd6b2707", "sync_status": [ ""... # truncating the output here ], "period_map": { "id": "b5e4d3ec-2a62-4746-b479-4b2bc14b27d1", "zonegroups": [ { "id": "d4018b8d-8c0d-4072-8919-608726fa369e", "name": "us", "api_name": "us", "is_master": "true", "endpoints": [ "http:\/\/rgw1:80" ], "hostnames": [], "hostnames_s3website": [], "master_zone": "83859a9a-9901-4f00-aa6d-285c777e10f0", "zones": [ { "id": "83859a9a-9901-4f00-aa6d-285c777e10f0", "name": "us-east-1", "endpoints": [ "http:\/\/rgw1:80" ], "log_meta": "true", "log_data": "false", "bucket_index_max_shards": 0, "read_only": "false" }, { "id": "950c1a43-6836-41a2-a161-64777e07e8b8", "name": "us-east-2", "endpoints": [ "http:\/\/rgw2:80" ], "log_meta": "false", "log_data": "true", "bucket_index_max_shards": 0, "read_only": "false" } ], "placement_targets": [ { "name": "default-placement", "tags": [] } ], "default_placement": "default-placement", "realm_id": "4a367026-bd8f-40ee-b486-8212482ddcd7" } ], "short_zone_ids": [ { "key": "83859a9a-9901-4f00-aa6d-285c777e10f0", "val": 630926044 }, { "key": "950c1a43-6836-41a2-a161-64777e07e8b8", "val": 4276257543 } ] }, "master_zonegroup": "d4018b8d-8c0d-4072-8919-608726fa369e", "master_zone": "83859a9a-9901-4f00-aa6d-285c777e10f0", "period_config": { "bucket_quota": { "enabled": false, "max_size_kb": -1, "max_objects": -1 }, "user_quota": { "enabled": false, "max_size_kb": -1, "max_objects": -1 } }, "realm_id": "4a367026-bd8f-40ee-b486-8212482ddcd7", "realm_name": "gold", "realm_epoch": 2 } Starting the Ceph Object Gateway instance ----------------------------------------- On the node that is hosting the Ceph Object Gateway instance of the second zone, you would start it, similar to the Ceph Object Gateway instance ``client.rgw.us-east-1`` , changing the ``rgw zone=us-east-2`` in the configuration file this time. For eg:: [client.rgw.us-east-2] rgw_frontends="civetweb port=80" rgw_zone=us-east-2 And start the Ceph Object Gateway instance depending on your Operating system's init system, for eg:: $ sudo systemctl start ceph-radosgw@rgw.us-east-2 Configuring the Ceph Object Gateway in the second Ceph cluster ============================================================== Now we go on to configure Ceph Object Gateway in the second Ceph cluster, which may be geographically apart, that is a part of the same zonegroup. Since a realm was already configured from the first cluster, we pull and make that realm as the default here, We also get the configuration from the master zone by pulling the period:: # radosgw-admin realm pull --url=http://rgw1:80 --access-key=$SYSTEM_ACCESS_KEY --secret=$SYSTEM_SECRET_KEY { "id": "4a367026-bd8f-40ee-b486-8212482ddcd7", "name": "gold", "current_period": "b5e4d3ec-2a62-4746-b479-4b2bc14b27d1", "epoch": 2 } # radosgw-admin period pull --url=http://rgw1:80 --access-key=$SYSTEM_ACCESS_KEY --secret=$SYSTEM_SECRET_KEY # radosgw-admin realm default --rgw-realm=gold We also set the default zonegroup to the created ``us`` zonegroup:: # radosgw-admin zonegroup default --rgw-zonegroup=us Configuring the second zone --------------------------- We create the new zone, ``us-west``, with the same system keys:: # radosgw-admin zone create --rgw-zonegroup=us --rgw-zone=us-west --access-key=$SYSTEM_ACCESS_KEY --secret=$SYSTEM_SECRET_KEY --endpoints=http://rgw3:80 --default { "id": "d9522067-cb7b-4129-8751-591e45815b16", "name": "us-west", "domain_root": "us-west.rgw.data.root", "control_pool": "us-west.rgw.control", "gc_pool": "us-west.rgw.gc", "log_pool": "us-west.rgw.log", "intent_log_pool": "us-west.rgw.intent-log", "usage_log_pool": "us-west.rgw.usage", "user_keys_pool": "us-west.rgw.users.keys", "user_email_pool": "us-west.rgw.users.email", "user_swift_pool": "us-west.rgw.users.swift", "user_uid_pool": "us-west.rgw.users.uid", "system_key": { "access_key": "1555b35654ad1656d804", "secret_key": "h7GhxuBLTrlhVUyxSPUKUV8r\/2EI4ngqJxD7iBdBYLhwluN30JaT3Q==" }, "placement_pools": [ { "key": "default-placement", "val": { "index_pool": "us-west.rgw.buckets.index", "data_pool": "us-west.rgw.buckets.data", "data_extra_pool": "us-west.rgw.buckets.non-ec", "index_type": 0 } } ], "metadata_heap": "us-west.rgw.meta", "realm_id": "4a367026-bd8f-40ee-b486-8212482ddcd7" } Updating the period ------------------- In order to propagate the zonegroup-map changes, we need to update and commit the period:: # radosgw-admin period update --commit --rgw-zone=us-west { "id": "b5e4d3ec-2a62-4746-b479-4b2bc14b27d1", "epoch": 3, "predecessor_uuid": "09559832-67a4-4101-8b3f-10dfcd6b2707", "sync_status": [ "", # truncated ], "period_map": { "id": "b5e4d3ec-2a62-4746-b479-4b2bc14b27d1", "zonegroups": [ { "id": "d4018b8d-8c0d-4072-8919-608726fa369e", "name": "us", "api_name": "us", "is_master": "true", "endpoints": [ "http:\/\/rgw1:80" ], "hostnames": [], "hostnames_s3website": [], "master_zone": "83859a9a-9901-4f00-aa6d-285c777e10f0", "zones": [ { "id": "83859a9a-9901-4f00-aa6d-285c777e10f0", "name": "us-east-1", "endpoints": [ "http:\/\/rgw1:80" ], "log_meta": "true", "log_data": "true", "bucket_index_max_shards": 0, "read_only": "false" }, { "id": "950c1a43-6836-41a2-a161-64777e07e8b8", "name": "us-east-2", "endpoints": [ "http:\/\/rgw2:80" ], "log_meta": "false", "log_data": "true", "bucket_index_max_shards": 0, "read_only": "false" }, { "id": "d9522067-cb7b-4129-8751-591e45815b16", "name": "us-west", "endpoints": [ "http:\/\/rgw3:80" ], "log_meta": "false", "log_data": "true", "bucket_index_max_shards": 0, "read_only": "false" } ], "placement_targets": [ { "name": "default-placement", "tags": [] } ], "default_placement": "default-placement", "realm_id": "4a367026-bd8f-40ee-b486-8212482ddcd7" } ], "short_zone_ids": [ { "key": "83859a9a-9901-4f00-aa6d-285c777e10f0", "val": 630926044 }, { "key": "950c1a43-6836-41a2-a161-64777e07e8b8", "val": 4276257543 }, { "key": "d9522067-cb7b-4129-8751-591e45815b16", "val": 329470157 } ] }, "master_zonegroup": "d4018b8d-8c0d-4072-8919-608726fa369e", "master_zone": "83859a9a-9901-4f00-aa6d-285c777e10f0", "period_config": { "bucket_quota": { "enabled": false, "max_size_kb": -1, "max_objects": -1 }, "user_quota": { "enabled": false, "max_size_kb": -1, "max_objects": -1 } }, "realm_id": "4a367026-bd8f-40ee-b486-8212482ddcd7", "realm_name": "gold", "realm_epoch": 2 } You can observe that the period epoch number has incremented, indicating a change in the configuration. Starting the Ceph Object Gateway instance ----------------------------------------- This is similar to starting the Ceph Object Gateway instance in the first zone, the only difference is the ``rgw zone`` option, which should reflect ``us-west``:: [client.rgw.us-west] rgw_frontends="civetweb port=80" rgw_zone=us-west And start the Ceph Object Gateway instance depending on your Operating system's init system, for eg:: $ sudo systemctl start ceph-radosgw@rgw.us-west .. _`Ceph Object Gateway - Create Pools`: ../config#create-pools .. _`Install Ceph Gateway`: ../../install/install-ceph-gateway