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@@ -13,11 +13,10 @@ This makes the storage disk requirements very predictable: only the number of _p
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DS _backend_ is a callback module that implements `emqx_ds` behavior.
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-EMQX repository contains the "builtin" backend, implemented in `emqx_ds_replication_layer` module, that uses Raft algorithm for data replication, and RocksDB as the main storage.
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+EMQX repository contains two builtin backends based on RocksDB:
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-Note that builtin backend introduces the concept of **site** to alleviate the problem of changing node names.
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-Site IDs are persistent, and they are randomly generated at the first startup of the node.
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-Each node in the cluster has a unique site ID, that is independent from the Erlang node name (`emqx@...`).
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+- `emqx_ds_builtin_local`
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+- `emqx_ds_builtin_raft`
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### Layout
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@@ -113,8 +112,8 @@ In the future it can serve as a storage for retained messages or as a generic me
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# Configurations
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-Global options for `emqx_durable_storage` application are configured via OTP application environment.
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-Database-specific settings are stored in the schema table.
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+Common global options for builtin backends are configured via OTP application environment.
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+Database-specific settings are stored in EMQX config.
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The following application environment variables are available:
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@@ -124,26 +123,9 @@ The following application environment variables are available:
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- `emqx_durable_storage.egress_flush_interval`: period at which the batches of messages are committed to the durable storage.
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-- `emqx_durable_storage.reads`: `leader_preferred` | `local_preferred`.
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-
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-Runtime settings for the durable storages can be modified via CLI as well as the REST API.
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-The following CLI commands are available:
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-
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-- `emqx ctl ds info` — get a quick overview of the durable storage state
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-- `emqx ctl ds set_replicas <DS> <Site1> <Site2> ...` — update the list of replicas for a durable storage.
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-- `emqx ctl ds join <DS> <Site>` — add a replica of durable storage on the site
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-- `emqx ctl ds leave <DS> <Site>` — remove a replica of a durable storage from the site
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-
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# HTTP APIs
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-The following REST APIs are available for managing the builtin durable storages:
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-
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-- `/ds/sites` — list known sites.
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-- `/ds/sites/:site` — get information about the site (its status, current EMQX node name managing the site, etc.)
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-- `/ds/storages` — list durable storages
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-- `/ds/storages/:ds` — get information about the durable storage and its shards
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-- `/ds/storages/:ds/replicas` — list or update sites that contain replicas of a durable storage
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-- `/ds/storages/:ds/replicas/:site` — add or remove replica of the durable storage on the site
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+None
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# Other
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