garage/doc/book/src/reference_manual/configuration.md

Garage configuration file format reference

Here is an example garage.toml configuration file that illustrates all of the possible options:

metadata_dir = "/var/lib/garage/meta"
data_dir = "/var/lib/garage/data"

block_size = 1048576

replication_mode = "3"

rpc_bind_addr = "[::]:3901"

bootstrap_peers = [
  "[fc00:1::1]:3901",
  "[fc00:1::2]:3901",
  "[fc00:B::1]:3901",
  "[fc00:F::1]:3901",
]

consul_host = "consul.service"
consul_service_name = "garage-daemon"

max_concurrent_rpc_requests = 12

sled_cache_capacity = 134217728
sled_flush_every_ms = 2000

[rpc_tls]
ca_cert = "/etc/garage/pki/garage-ca.crt"
node_cert = "/etc/garage/pki/garage.crt"
node_key = "/etc/garage/pki/garage.key"

[s3_api]
s3_region = "garage"
api_bind_addr = "[::]:3900"

[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.

block_size

Garage splits stored objects in consecutive chunks of size block_size (except the last one which might be standard). 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!)

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.

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.

bootstrap_peers

A list of IPs and ports on which to contact other Garage peers of this cluster. This should correspond to the RPC ports set up with rpc_bind_addr.

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.

max_concurrent_rpc_requests

Garage implements rate limiting for RPC requests: no more than max_concurrent_rpc_requests concurrent outbound RPC requests will be made by a Garage node (additionnal requests will be put in a waiting queue).

sled_cache_capacity

This parameter can be used to tune the capacity of the cache used by sled, 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 [rpc_tls] section

This section should be used to configure the TLS certificates used to encrypt intra-cluster traffic (RPC traffic). The following parameters should be set:

• ca_cert: the certificate of the CA that is allowed to sign individual node certificates
• node_cert: the node certificate for the current node
• node_key: the key associated with the node certificate

Note tha several nodes may use the same node certificate, as long as it is signed by the CA.

If this section is absent, TLS is not used to encrypt intra-cluster traffic.

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.

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).