Install Keepstore servers

We are going to install two Keepstore servers. By convention, we use the following hostname pattern:


Because the Keepstore servers are not directly accessible from the internet, these hostnames only need to resolve on the local network.

Install Keepstore

On Debian-based systems:

~$ sudo apt-get install keepstore

On Red Hat-based systems:

~$ sudo yum install keepstore

Verify that Keepstore is functional:

~$ keepstore -h
2016/07/01 14:06:21 keepstore starting, pid 32339
Usage of ./keepstore:
  -azure-max-get-bytes int
    	Maximum bytes to request in a single GET request. If smaller than 67108864, use multiple concurrent range requests to retrieve a block. (default 67108864)
  -azure-storage-account-key-file string
    	File containing the account key used for subsequent --azure-storage-container-volume arguments.
  -azure-storage-account-name string
    	Azure storage account name used for subsequent --azure-storage-container-volume arguments.
  -azure-storage-container-volume value
    	Use the given container as a storage volume. Can be given multiple times. (default [])
  -azure-storage-replication int
    	Replication level to report to clients when data is stored in an Azure container. (default 3)
  -blob-signature-ttl int
    	Lifetime of blob permission signatures in seconds. Modifying the ttl will invalidate all existing signatures. See services/api/config/application.default.yml. (default 1209600)
  -blob-signing-key-file string
    	File containing the secret key for generating and verifying blob permission signatures.
  -data-manager-token-file string
    	File with the API token used by the Data Manager. All DELETE requests or GET /index requests must carry this token.
    	Enforce permission signatures on requests.
  -listen string
    	Listening address, in the form "host:port". e.g., Omit the host part to listen on all interfaces. (default ":25107")
  -max-buffers int
    	Maximum RAM to use for data buffers, given in multiples of block size (64 MiB). When this limit is reached, HTTP requests requiring buffers (like GET and PUT) will wait for buffer space to be released. (default 128)
  -max-requests int
    	Maximum concurrent requests. When this limit is reached, new requests will receive 503 responses. Note: this limit does not include idle connections from clients using HTTP keepalive, so it does not strictly limit the number of concurrent connections. (default 2 * max-buffers)
    	If true, nothing will be deleted. Warning: the relevant features in keepstore and data manager have not been extensively tested. You should leave this option alone unless you can afford to lose data. (default true)
  -permission-key-file string
    	Synonym for -blob-signing-key-file.
  -permission-ttl int
    	Synonym for -blob-signature-ttl.
  -pid fuser -k pidfile
    	Path to write pid file during startup. This file is kept open and locked with LOCK_EX until keepstore exits, so fuser -k pidfile is one way to shut down. Exit immediately if there is an error opening, locking, or writing the pid file.
    	Do not write, delete, or touch anything on the following volumes.
  -s3-access-key-file string
    	File containing the access key used for subsequent -s3-bucket-volume arguments.
  -s3-bucket-volume value
    	Use the given bucket as a storage volume. Can be given multiple times. (default [])
  -s3-endpoint string
    	Endpoint URL used for subsequent -s3-bucket-volume arguments. If blank, use the AWS endpoint corresponding to the -s3-region argument. For Google Storage, use "".
  -s3-region string
    	AWS region used for subsequent -s3-bucket-volume arguments. Allowed values are ["ap-southeast-1" "eu-west-1" "us-gov-west-1" "sa-east-1" "cn-north-1" "ap-northeast-1" "ap-southeast-2" "eu-central-1" "us-east-1" "us-west-1" "us-west-2"].
  -s3-replication int
    	Replication level reported to clients for subsequent -s3-bucket-volume arguments. (default 2)
  -s3-secret-key-file string
    	File containing the secret key used for subsequent -s3-bucket-volume arguments.
    	EXPERIMENTAL. Enable deletion (garbage collection), even though there are known race conditions that can cause data loss.
    	Serialize read and write operations on the following volumes.
  -trash-check-interval duration
    	Time duration at which the emptyTrash goroutine will check and delete expired trashed blocks. Default is one day. (default 24h0m0s)
  -trash-lifetime duration
    	Time duration after a block is trashed during which it can be recovered using an /untrash request
  -volume value
    	Local storage directory. Can be given more than once to add multiple directories. If none are supplied, the default is to use all directories named "keep" that exist in the top level directory of a mount point at startup time. Can be a comma-separated list, but this is deprecated: use multiple -volume arguments instead. (default [])
  -volumes value
    	Deprecated synonym for -volume. (default [])

Prepare storage volumes


This section uses a local filesystem as a backing store. If you are using Azure Storage, follow the setup instructions on the Azure Blob Storage page instead.

There are two ways to specify a set of local directories where keepstore should store its data files.

  1. Implicitly, by creating a directory called keep at the top level of each filesystem you intend to use, and omitting -volume arguments.
  2. Explicitly, by providing a -volume argument for each directory.

For example, if there are filesystems mounted at /mnt and /mnt2:

~$ mkdir /mnt/keep /mnt2/keep
~$ keepstore
2015/05/08 13:44:26 keepstore starting, pid 2765
2015/05/08 13:44:26 Using volume [UnixVolume /mnt/keep] (writable=true)
2015/05/08 13:44:26 Using volume [UnixVolume /mnt2/keep] (writable=true)
2015/05/08 13:44:26 listening at :25107


~$ mkdir /mnt/keep /mnt2/keep
~$ keepstore -volume=/mnt/keep -volume=/mnt2/keep
2015/05/08 13:44:26 keepstore starting, pid 2765
2015/05/08 13:44:26 Using volume [UnixVolume /mnt/keep] (writable=true)
2015/05/08 13:44:26 Using volume [UnixVolume /mnt2/keep] (writable=true)
2015/05/08 13:44:26 listening at :25107

Run keepstore as a supervised service

Install runit to supervise the keepstore daemon.

On Debian-based systems:

~$ sudo apt-get install runit

On Red Hat-based systems:

~$ sudo yum install runit

Install this script as the run script for the keepstore service, modifying it as directed below.


exec 2>&1
exec GOGC=10 keepstore \
 -enforce-permissions=true \
 -blob-signing-key-file=/etc/keepstore/blob-signing.key \
 -max-buffers=100 \
 -serialize=true \
 -never-delete=false \
 -volume=/mnt/keep \

The -max-buffers argument limits keepstore’s memory usage. It should be set such that max-buffers * 64MiB + 10% fits comfortably in memory. On a host dedicated to running keepstore, divide total memory by 88MiB to suggest a suitable value. For example, if grep MemTotal /proc/meminfo reports MemTotal: 7125440 kB, compute 7125440÷(88×1024)=79 and configure -max-buffers=79.

If you want access control on your Keepstore server(s), you must specify the -enforce-permissions flag and provide a signing key. The -blob-signing-key-file argument should be a file containing a long random alphanumeric string with no internal line breaks (it is also possible to use a socket or FIFO: keepstore reads it only once, at startup). This key must be the same as the blob_signing_key configured in the API server’s configuration file, /etc/arvados/api/application.yml.

The -serialize=true (default: false) argument limits keepstore to one reader/writer process per storage partition. This avoids thrashing by allowing the storage device underneath the storage partition to do read/write operations sequentially. Enabling -serialize can improve Keepstore performance if the storage partitions map 1:1 to physical disks that are dedicated to Keepstore, particularly so for mechanical disks. In some cloud environments, enabling -serialize has also also proven to be beneficial for performance, but YMMV. If your storage partition(s) are backed by network or RAID storage that can handle many simultaneous reader/writer processes without thrashing, you probably do not want to set -serialize.

Set up additional servers

Repeat the above sections to prepare volumes and bring up supervised services on each Keepstore server you are setting up.

Tell the API server about the Keepstore servers

The API server needs to be informed about the presence of your Keepstore servers. For each of the Keepstore servers you have created, please execute the following commands on your shell server.

Make sure to update the service_host value to match each of your Keepstore servers.

~$ prefix=`arv --format=uuid user current | cut -d- -f1`
~$ echo "Site prefix is '$prefix'"
~$ read -rd $'\000' keepservice <<EOF; arv keep_service create --keep-service "$keepservice"

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Code samples in this documentation are licensed under the Apache License, Version 2.0.