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author | Alex Auvolat <alex@adnab.me> | 2022-02-02 10:05:27 +0100 |
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committer | Alex Auvolat <alex@adnab.me> | 2022-02-07 11:47:51 +0100 |
commit | ff04afaa771e1ec2bd482fa47ced1a8e4933c916 (patch) | |
tree | c2e0962ed5e672aea733607e4c16ac37e3b2b40d /doc/book/reference-manual | |
parent | 45d6d377d2011d8fb4ceb13bb4584df97c458525 (diff) | |
download | garage-ff04afaa771e1ec2bd482fa47ced1a8e4933c916.tar.gz garage-ff04afaa771e1ec2bd482fa47ced1a8e4933c916.zip |
Move documentation files around and adapt format for new website
Diffstat (limited to 'doc/book/reference-manual')
-rw-r--r-- | doc/book/reference-manual/_index.md | 10 | ||||
-rw-r--r-- | doc/book/reference-manual/cli.md | 7 | ||||
-rw-r--r-- | doc/book/reference-manual/configuration.md | 240 | ||||
-rw-r--r-- | doc/book/reference-manual/layout.md | 77 | ||||
-rw-r--r-- | doc/book/reference-manual/s3_compatibility.md | 67 |
5 files changed, 401 insertions, 0 deletions
diff --git a/doc/book/reference-manual/_index.md b/doc/book/reference-manual/_index.md new file mode 100644 index 00000000..62716df8 --- /dev/null +++ b/doc/book/reference-manual/_index.md @@ -0,0 +1,10 @@ ++++ +title = "Reference Manual" +weight = 4 +sort_by = "weight" +template = "documentation.html" ++++ + +A reference manual contains some extensive descriptions about the features and the behaviour of the software. +Reading of this chapter is recommended once you have a good knowledge/understanding of Garage. +It will be useful if you want to tune it or to use it in some exotic conditions. diff --git a/doc/book/reference-manual/cli.md b/doc/book/reference-manual/cli.md new file mode 100644 index 00000000..43a0c823 --- /dev/null +++ b/doc/book/reference-manual/cli.md @@ -0,0 +1,7 @@ ++++ +title = "Garage CLI" +weight = 15 ++++ + +The Garage CLI is mostly self-documented. Make use of the `help` subcommand +and the `--help` flag to discover all available options. diff --git a/doc/book/reference-manual/configuration.md b/doc/book/reference-manual/configuration.md new file mode 100644 index 00000000..b9c093aa --- /dev/null +++ b/doc/book/reference-manual/configuration.md @@ -0,0 +1,240 @@ ++++ +title = "Configuration file format" +weight = 5 ++++ + +Here is an example `garage.toml` configuration file that illustrates all of the possible options: + +```toml +metadata_dir = "/var/lib/garage/meta" +data_dir = "/var/lib/garage/data" + +block_size = 1048576 + +replication_mode = "3" + +compression_level = 1 + +rpc_secret = "4425f5c26c5e11581d3223904324dcb5b5d5dfb14e5e7f35e38c595424f5f1e6" +rpc_bind_addr = "[::]:3901" +rpc_public_addr = "[fc00:1::1]:3901" + +bootstrap_peers = [ + "563e1ac825ee3323aa441e72c26d1030d6d4414aeb3dd25287c531e7fc2bc95d@[fc00:1::1]:3901", + "86f0f26ae4afbd59aaf9cfb059eefac844951efd5b8caeec0d53f4ed6c85f332[fc00:1::2]:3901", + "681456ab91350f92242e80a531a3ec9392cb7c974f72640112f90a600d7921a4@[fc00:B::1]:3901", + "212fd62eeaca72c122b45a7f4fa0f55e012aa5e24ac384a72a3016413fa724ff@[fc00:F::1]:3901", +] + +consul_host = "consul.service" +consul_service_name = "garage-daemon" + +sled_cache_capacity = 134217728 +sled_flush_every_ms = 2000 + +[s3_api] +api_bind_addr = "[::]:3900" +s3_region = "garage" +root_domain = ".s3.garage" + +[s3_web] +bind_addr = "[::]:3902" +root_domain = ".web.garage" +index = "index.html" +``` + +The following gives details about each available configuration option. + +## Available configuration options + +#### `metadata_dir` + +The directory in which Garage will store its metadata. This contains the node identifier, +the network configuration and the peer list, the list of buckets and keys as well +as the index of all objects, object version and object blocks. + +Store this folder on a fast SSD drive if possible to maximize Garage's performance. + +#### `data_dir` + +The directory in which Garage will store the data blocks of objects. +This folder can be placed on an HDD. The space available for `data_dir` +should be counted to determine a node's capacity +when [configuring it](../getting_started/05_cluster.md). + +#### `block_size` + +Garage splits stored objects in consecutive chunks of size `block_size` +(except the last one which might be smaller). The default size is 1MB and +should work in most cases. If you are interested in tuning this, feel free +to do so (and remember to report your findings to us!). If this value is +changed for a running Garage installation, only files newly uploaded will be +affected. Previously uploaded files will remain available. This however +means that chunks from existing files will not be deduplicated with chunks +from newly uploaded files, meaning you might use more storage space that is +optimally possible. + +#### `replication_mode` + +Garage supports the following replication modes: + +- `none` or `1`: data stored on Garage is stored on a single node. There is no redundancy, + and data will be unavailable as soon as one node fails or its network is disconnected. + Do not use this for anything else than test deployments. + +- `2`: data stored on Garage will be stored on two different nodes, if possible in different + zones. Garage tolerates one node failure before losing data. Data should be available + read-only when one node is down, but write operations will fail. + Use this only if you really have to. + +- `3`: data stored on Garage will be stored on three different nodes, if possible each in + a different zones. + Garage tolerates two node failure before losing data. Data should be available + read-only when two nodes are down, and writes should be possible if only a single node + is down. + +Note that in modes `2` and `3`, +if at least the same number of zones are available, an arbitrary number of failures in +any given zone is tolerated as copies of data will be spread over several zones. + +**Make sure `replication_mode` is the same in the configuration files of all nodes. +Never run a Garage cluster where that is not the case.** + +Changing the `replication_mode` of a cluster might work (make sure to shut down all nodes +and changing it everywhere at the time), but is not officially supported. + +### `compression_level` + +Zstd compression level to use for storing blocks. + +Values between `1` (faster compression) and `19` (smaller file) are standard compression +levels for zstd. From `20` to `22`, compression levels are referred as "ultra" and must be +used with extra care as it will use lot of memory. A value of `0` will let zstd choose a +default value (currently `3`). Finally, zstd has also compression designed to be faster +than default compression levels, they range from `-1` (smaller file) to `-99` (faster +compression). + +If you do not specify a `compression_level` entry, garage will set it to `1` for you. With +this parameters, zstd consumes low amount of cpu and should work faster than line speed in +most situations, while saving some space and intra-cluster +bandwidth. + +If you want to totally deactivate zstd in garage, you can pass the special value `'none'`. No +zstd related code will be called, your chunks will be stored on disk without any processing. + +Compression is done synchronously, setting a value too high will add latency to write queries. + +This value can be different between nodes, compression is done by the node which receive the +API call. + +#### `rpc_secret` + +Garage uses a secret key that is shared between all nodes of the cluster +in order to identify these nodes and allow them to communicate together. +This key should be specified here in the form of a 32-byte hex-encoded +random string. Such a string can be generated with a command +such as `openssl rand -hex 32`. + +#### `rpc_bind_addr` + +The address and port on which to bind for inter-cluster communcations +(reffered to as RPC for remote procedure calls). +The port specified here should be the same one that other nodes will used to contact +the node, even in the case of a NAT: the NAT should be configured to forward the external +port number to the same internal port nubmer. This means that if you have several nodes running +behind a NAT, they should each use a different RPC port number. + +#### `rpc_public_addr` + +The address and port that other nodes need to use to contact this node for +RPC calls. **This parameter is optional but recommended.** In case you have +a NAT that binds the RPC port to a port that is different on your public IP, +this field might help making it work. + +#### `bootstrap_peers` + +A list of peer identifiers on which to contact other Garage peers of this cluster. +These peer identifiers have the following syntax: + +``` +<node public key>@<node public IP or hostname>:<port> +``` + +In the case where `rpc_public_addr` is correctly specified in the +configuration file, the full identifier of a node including IP and port can +be obtained by running `garage node id` and then included directly in the +`bootstrap_peers` list of other nodes. Otherwise, only the node's public +key will be returned by `garage node id` and you will have to add the IP +yourself. + +#### `consul_host` and `consul_service_name` + +Garage supports discovering other nodes of the cluster using Consul. +This works only when nodes are announced in Consul by an orchestrator such as Nomad, +as Garage is not able to announce itself. + +The `consul_host` parameter should be set to the hostname of the Consul server, +and `consul_service_name` should be set to the service name under which Garage's +RPC ports are announced. + +#### `sled_cache_capacity` + +This parameter can be used to tune the capacity of the cache used by +[sled](https://sled.rs), the database Garage uses internally to store metadata. +Tune this to fit the RAM you wish to make available to your Garage instance. +More cache means faster Garage, but the default value (128MB) should be plenty +for most use cases. + +#### `sled_flush_every_ms` + +This parameters can be used to tune the flushing interval of sled. +Increase this if sled is thrashing your SSD, at the risk of losing more data in case +of a power outage (though this should not matter much as data is replicated on other +nodes). The default value, 2000ms, should be appropriate for most use cases. + + +## The `[s3_api]` section + +#### `api_bind_addr` + +The IP and port on which to bind for accepting S3 API calls. +This endpoint does not suport TLS: a reverse proxy should be used to provide it. + +#### `s3_region` + +Garage will accept S3 API calls that are targetted to the S3 region defined here. +API calls targetted to other regions will fail with a AuthorizationHeaderMalformed error +message that redirects the client to the correct region. + +#### `root_domain` + +The optionnal suffix to access bucket using vhost-style in addition to path-style request. +Note path-style requests are always enabled, whether or not vhost-style is configured. +Configuring vhost-style S3 required a wildcard DNS entry, and possibly a wildcard TLS certificate, +but might be required by softwares not supporting path-style requests. + +If `root_domain` is `s3.garage.eu`, a bucket called `my-bucket` can be interacted with +using the hostname `my-bucket.s3.garage.eu`. + +## The `[s3_web]` section + +Garage allows to publish content of buckets as websites. This section configures the +behaviour of this module. + +#### `bind_addr` + +The IP and port on which to bind for accepting HTTP requests to buckets configured +for website access. +This endpoint does not suport TLS: a reverse proxy should be used to provide it. + +#### `root_domain` + +The optionnal suffix appended to bucket names for the corresponding HTTP Host. + +For instance, if `root_domain` is `web.garage.eu`, a bucket called `deuxfleurs.fr` +will be accessible either with hostname `deuxfleurs.fr.web.garage.eu` +or with hostname `deuxfleurs.fr`. + +#### `index` + +The name of the index file to return for requests ending with `/` (usually `index.html`). diff --git a/doc/book/reference-manual/layout.md b/doc/book/reference-manual/layout.md new file mode 100644 index 00000000..3f818b62 --- /dev/null +++ b/doc/book/reference-manual/layout.md @@ -0,0 +1,77 @@ ++++ +title = "Cluster layout management" +weight = 10 ++++ + +The cluster layout in Garage is a table that assigns to each node a role in +the cluster. The role of a node in Garage can either be a storage node with +a certain capacity, or a gateway node that does not store data and is only +used as an API entry point for faster cluster access. +An introduction to building cluster layouts can be found in the [production deployment](/cookbook/real_world.md) page. + +## How cluster layouts work in Garage + +In Garage, a cluster layout is composed of the following components: + +- a table of roles assigned to nodes +- a version number + +Garage nodes will always use the cluster layout with the highest version number. + +Garage nodes also maintain and synchronize between them a set of proposed role +changes that haven't yet been applied. These changes will be applied (or +canceled) in the next version of the layout + +The following commands insert modifications to the set of proposed role changes +for the next layout version (but they do not create the new layout immediately): + +```bash +garage layout assign [...] +garage layout remove [...] +``` + +The following command can be used to inspect the layout that is currently set in the cluster +and the changes proposed for the next layout version, if any: + +```bash +garage layout show +``` + +The following commands create a new layout with the specified version number, +that either takes into account the proposed changes or cancels them: + +```bash +garage layout apply --version <new_version_number> +garage layout revert --version <new_version_number> +``` + +The version number of the new layout to create must be 1 + the version number +of the previous layout that existed in the cluster. The `apply` and `revert` +commands will fail otherwise. + +## Warnings about Garage cluster layout management + +**Warning: never make several calls to `garage layout apply` or `garage layout +revert` with the same value of the `--version` flag. Doing so can lead to the +creation of several different layouts with the same version number, in which +case your Garage cluster will become inconsistent until fixed.** If a call to +`garage layout apply` or `garage layout revert` has failed and `garage layout +show` indicates that a new layout with the given version number has not been +set in the cluster, then it is fine to call the command again with the same +version number. + +If you are using the `garage` CLI by typing individual commands in your +shell, you shouldn't have much issues as long as you run commands one after +the other and take care of checking the output of `garage layout show` +before applying any changes. + +If you are using the `garage` CLI to script layout changes, follow the following recommendations: + +- Make all of your `garage` CLI calls to the same RPC host. Do not use the + `garage` CLI to connect to individual nodes to send them each a piece of the + layout changes you are making, as the changes propagate asynchronously + between nodes and might not all be taken into account at the time when the + new layout is applied. + +- **Only call `garage layout apply` once**, and call it **strictly after** all + of the `layout assign` and `layout remove` commands have returned. diff --git a/doc/book/reference-manual/s3_compatibility.md b/doc/book/reference-manual/s3_compatibility.md new file mode 100644 index 00000000..fdac06ab --- /dev/null +++ b/doc/book/reference-manual/s3_compatibility.md @@ -0,0 +1,67 @@ ++++ +title = "S3 Compatibility status" +weight = 20 ++++ + +## Global S3 features + +Implemented: + +- path-style URLs (`garage.tld/bucket/key`) +- vhost-style URLs (`bucket.garage.tld/key`) +- putting and getting objects in buckets +- multipart uploads +- listing objects +- access control on a per-access-key-per-bucket basis +- CORS headers on web endpoint + +Not implemented: + +- object-level ACL +- [object versioning](https://git.deuxfleurs.fr/Deuxfleurs/garage/issues/166) +- encryption +- most `x-amz-` headers + + +## Endpoint implementation + +All APIs that are not mentionned are not implemented and will return a 501 Not Implemented. + +| Endpoint | Status | +|------------------------------|----------------------------------| +| AbortMultipartUpload | Implemented | +| CompleteMultipartUpload | Implemented | +| CopyObject | Implemented | +| CreateBucket | Implemented | +| CreateMultipartUpload | Implemented | +| DeleteBucket | Implemented | +| DeleteBucketCors | Implemented | +| DeleteBucketWebsite | Implemented | +| DeleteObject | Implemented | +| DeleteObjects | Implemented | +| GetBucketCors | Implemented | +| GetBucketLocation | Implemented | +| GetBucketVersioning | Stub (see below) | +| GetBucketWebsite | Implemented | +| GetObject | Implemented | +| HeadBucket | Implemented | +| HeadObject | Implemented | +| ListBuckets | Implemented | +| ListObjects | Implemented, bugs? (see below) | +| ListObjectsV2 | Implemented | +| ListMultipartUpload | Implemented | +| ListParts | Implemented | +| PutObject | Implemented | +| PutBucketCors | Implemented | +| PutBucketWebsite | Partially implemented (see below)| +| UploadPart | Implemented | +| UploadPartCopy | Implemented | + + +- **GetBucketVersioning:** Stub implementation (Garage does not yet support versionning so this always returns +"versionning not enabled"). + +- **ListObjects:** Implemented, but there isn't a very good specification of what `encoding-type=url` covers so there might be some encoding bugs. In our implementation the url-encoded fields are in the same in ListObjects as they are in ListObjectsV2. + +- **PutBucketWebsite:** Implemented, but only stores the index document suffix and the error document path. Redirects are not supported. + |