files/gitlab-cookbooks/gitlab-ee/templates/default/sentinel.conf.erb

# This file is managed by gitlab-ctl. Manual changes will be
# erased! To change the contents below, edit /etc/gitlab/gitlab.rb
# and run `sudo gitlab-ctl reconfigure`.

# *** IMPORTANT ***
#
# By default Sentinel will not be reachable from interfaces different than
# localhost, either use the 'bind' directive to bind to a list of network
# interfaces, or disable protected mode with "protected-mode no" by
# adding it to this configuration file.
#
# Before doing that MAKE SURE the instance is protected from the outside
# world via firewalling or other means.
#
# For example you may use one of the following:
#
# bind 127.0.0.1 192.168.1.1
#
# protected-mode no
bind <%= @sentinel['bind'] %>

# port <sentinel-port>
# The port that this sentinel instance will run on
port <%= @sentinel['port'] %>

<%= "sentinel announce-ip #{@sentinel['announce_ip']}" if @sentinel['announce_ip'] %>
<%= "sentinel announce-port #{@sentinel['announce_port']}" if @sentinel['announce_port'] %>
#
# The above two configuration directives are useful in environments where,
# because of NAT, Sentinel is reachable from outside via a non-local address.
#
# When announce-ip is provided, the Sentinel will claim the specified IP address
# in HELLO messages used to gossip its presence, instead of auto-detecting the
# local address as it usually does.
#
# Similarly when announce-port is provided and is valid and non-zero, Sentinel
# will announce the specified TCP port.
#
# The two options don't need to be used together, if only announce-ip is
# provided, the Sentinel will announce the specified IP and the server port
# as specified by the "port" option. If only announce-port is provided, the
# Sentinel will announce the auto-detected local IP and the specified port.
#
# Example:
#
# sentinel announce-ip 1.2.3.4

# dir <working-directory>
# Every long running process should have a well-defined working directory.
# For Redis Sentinel to chdir to /tmp at startup is the simplest thing
# for the process to don't interfere with administrative tasks such as
# unmounting filesystems.
dir <%= %Q("#{@sentinel['dir']}") %>

# sentinel myid <id>
#
# Unique 40 hex-characters long identification of the instance in the cluster
# This value is spread across all sentinels and each instance keep a list of
# "known" instances to calculate majority in a failover consensus voting.
<%= "sentinel myid #{@sentinel['myid']}" if @sentinel['myid'] %>

# sentinel monitor <master-name> <ip> <redis-port> <quorum>
#
# Tells Sentinel to monitor this master, and to consider it in O_DOWN
# (Objectively Down) state only if at least <quorum> sentinels agree.
#
# Note that whatever is the ODOWN quorum, a Sentinel will require to
# be elected by the majority of the known Sentinels in order to
# start a failover, so no failover can be performed in minority.
#
# Replicas are auto-discovered, so you don't need to specify replicas in
# any way. Sentinel itself will rewrite this configuration file adding
# the replicas using additional configuration options.
# Also note that the configuration file is rewritten when a
# replica is promoted to master.
#
# Note: master name should not include special characters or spaces.
# The valid charset is A-z 0-9 and the three characters ".-_".
sentinel monitor <%= @redis['master_name'] %> <%= @redis['master_ip'] %> <%= @redis['master_port'] %> <%= @sentinel['quorum'] %>

# sentinel down-after-milliseconds <master-name> <milliseconds>
#
# Number of milliseconds the master (or any attached replica or sentinel) should
# be unreachable (as in, not acceptable reply to PING, continuously, for the
# specified period) in order to consider it in S_DOWN state (Subjectively
# Down).
#
# Default is 30 seconds.
sentinel down-after-milliseconds <%= @redis['master_name'] %> <%= @sentinel['down_after_milliseconds'] %>

# requirepass <password>
#
# You can configure Sentinel itself to require a password, however when doing
# so Sentinel will try to authenticate with the same password to all the
# other Sentinels. So you need to configure all your Sentinels in a given
# group with the same "requirepass" password. Check the following documentation
# for more info: https://redis.io/topics/sentinel
#
# IMPORTANT NOTE: starting with Redis 6.2 "requirepass" is a compatibility
# layer on top of the ACL system. The option effect will be just setting
# the password for the default user. Clients will still authenticate using
# AUTH <password> as usually, or more explicitly with AUTH default <password>
# if they follow the new protocol: both will work.
<%= %Q(requirepass "#{@sentinel['password']}") if @sentinel['password'] %>

# sentinel parallel-syncs <master-name> <numreplicas>
#
# How many replicas we can reconfigure to point to the new replica simultaneously
# during the failover. Use a low number if you use the replicas to serve query
# to avoid that all the replicas will be unreachable at about the same
# time while performing the synchronization with the master.
# sentinel parallel-syncs localhost 1

# sentinel failover-timeout <master-name> <milliseconds>
#
# Specifies the failover timeout in milliseconds. It is used in many ways:
#
# - The time needed to re-start a failover after a previous failover was
#   already tried against the same master by a given Sentinel, is two
#   times the failover timeout.
#
# - The time needed for a replica replicating to a wrong master according
#   to a Sentinel current configuration, to be forced to replicate
#   with the right master, is exactly the failover timeout (counting since
#   the moment a Sentinel detected the misconfiguration).
#
# - The time needed to cancel a failover that is already in progress but
#   did not produced any configuration change (REPLICAOF NO ONE yet not
#   acknowledged by the promoted replica).
#
# - The maximum time a failover in progress waits for all the replicas to be
#   reconfigured as replicas of the new master. However even after this time
#   the replicas will be reconfigured by the Sentinels anyway, but not with
#   the exact parallel-syncs progression as specified.
#
# Default is 3 minutes.
sentinel failover-timeout <%= @redis['master_name'] %> <%= @sentinel['failover_timeout'] %>

# sentinel auth-pass <master-name> <password>
#
# Set the password to use to authenticate with the master and replicas.
# Useful if there is a password set in the Redis instances to monitor.
#
# Note that the master password is also used for replicas, so it is not
# possible to set a different password in masters and replicas instances
# if you want to be able to monitor these instances with Sentinel.
#
# However you can have Redis instances without the authentication enabled
# mixed with Redis instances requiring the authentication (as long as the
# password set is the same for all the instances requiring the password) as
# the AUTH command will have no effect in Redis instances with authentication
# switched off.
#
# Example:
#
sentinel auth-pass <%= @redis['master_name'] %> <%= @redis['master_password'] %>

# SCRIPTS EXECUTION
#
# sentinel notification-script and sentinel reconfig-script are used in order
# to configure scripts that are called to notify the system administrator
# or to reconfigure clients after a failover. The scripts are executed
# with the following rules for error handling:
#
# If script exits with "1" the execution is retried later (up to a maximum
# number of times currently set to 10).
#
# If script exits with "2" (or an higher value) the script execution is
# not retried.
#
# If script terminates because it receives a signal the behavior is the same
# as exit code 1.
#
# A script has a maximum running time of 60 seconds. After this limit is
# reached the script is terminated with a SIGKILL and the execution retried.

# NOTIFICATION SCRIPT
#
# sentinel notification-script <master-name> <script-path>
#
# Call the specified notification script for any sentinel event that is
# generated in the WARNING level (for instance -sdown, -odown, and so forth).
# This script should notify the system administrator via email, SMS, or any
# other messaging system, that there is something wrong with the monitored
# Redis systems.
#
# The script is called with just two arguments: the first is the event type
# and the second the event description.
#
# The script must exist and be executable in order for sentinel to start if
# this option is provided.
#
# Example:
#
# sentinel notification-script mymaster /var/redis/notify.sh

# CLIENTS RECONFIGURATION SCRIPT
#
# sentinel client-reconfig-script <master-name> <script-path>
#
# When the master changed because of a failover a script can be called in
# order to perform application-specific tasks to notify the clients that the
# configuration has changed and the master is at a different address.
#
# The following arguments are passed to the script:
#
# <master-name> <role> <state> <from-ip> <from-port> <to-ip> <to-port>
#
# <state> is currently always "failover"
# <role> is either "leader" or "observer"
#
# The arguments from-ip, from-port, to-ip, to-port are used to communicate
# the old address of the master and the new address of the elected replica
# (now a master).
#
# This script should be resistant to multiple invocations.
#
# Example:
#
# sentinel client-reconfig-script mymaster /var/redis/reconfig.sh

################################# TLS/SSL #####################################

# By default, TLS/SSL is disabled. To enable it, the "tls-port" configuration
# directive can be used to define TLS-listening ports. To enable TLS on the
# default port, use:
#
# port 0
# tls-port 6379
# We enable TLS related settings only if tls_port is defined
<% unless @sentinel['tls_port'].nil? %>
tls-port <%= @sentinel['tls_port'] %>

# Configure a X.509 certificate and private key to use for authenticating the
# server to connected clients, masters or cluster peers.  These files should be
# PEM formatted.
#
# tls-cert-file redis.crt
<% unless @sentinel['tls_cert_file'].nil? %>
tls-cert-file <%= @sentinel['tls_cert_file'] %>
<% end %>
# tls-key-file redis.key
<% unless @sentinel['tls_key_file'].nil? %>
tls-key-file <%= @sentinel['tls_key_file'] %>
<% end %>

# Configure a DH parameters file to enable Diffie-Hellman (DH) key exchange:
#
# tls-dh-params-file redis.dh
<% unless @sentinel['tls_dh_params_file'].nil? %>
tls-dh-params-file <%= @sentinel['tls_dh_params_file'] %>
<% end %>

# Configure a CA certificate(s) bundle or directory to authenticate TLS/SSL
# clients and peers.  Redis requires an explicit configuration of at least one
# of these, and will not implicitly use the system wide configuration.
#
# tls-ca-cert-file ca.crt
<% unless @sentinel['tls_ca_cert_file'].nil? %>
tls-ca-cert-file <%= @sentinel['tls_ca_cert_file'] %>
<% end %>
# tls-ca-cert-dir /etc/ssl/certs
<% unless @sentinel['tls_ca_cert_dir'].nil? %>
tls-ca-cert-dir <%= @sentinel['tls_ca_cert_dir'] %>
<% end %>

# By default, clients (including replica servers) on a TLS port are required
# to authenticate using valid client side certificates.
#
# If "no" is specified, client certificates are not required and not accepted.
# If "optional" is specified, client certificates are accepted and must be
# valid if provided, but are not required.
#
# tls-auth-clients no
# tls-auth-clients optional
<% unless @sentinel['tls_auth_clients'].nil? %>
tls-auth-clients <%= @sentinel['tls_auth_clients'] %>
<% end %>

# By default, a Redis replica does not attempt to establish a TLS connection
# with its master.
#
# Use the following directive to enable TLS on replication links.
#
# tls-replication yes
<% unless @sentinel['tls_replication'].nil? %>
tls-replication <%= @sentinel['tls_replication'] %>
<% end %>

# By default, the Redis Cluster bus uses a plain TCP connection. To enable
# TLS for the bus protocol, use the following directive:
#
# tls-cluster yes
<% unless @sentinel['tls_cluster'].nil? %>
tls-cluster <%= @sentinel['tls_cluster'] %>
<% end %>

# Explicitly specify TLS versions to support. Allowed values are case insensitive
# and include "TLSv1", "TLSv1.1", "TLSv1.2", "TLSv1.3" (OpenSSL >= 1.1.1) or
# any combination. To enable only TLSv1.2 and TLSv1.3, use:
#
# tls-protocols "TLSv1.2 TLSv1.3"
<% unless @sentinel['tls_protocols'].nil? %>
tls-protocols "<%= @sentinel['tls_protocols'] %>"
<% end %>

# Configure allowed ciphers.  See the ciphers(1ssl) manpage for more information
# about the syntax of this string.
#
# Note: this configuration applies only to <= TLSv1.2.
#
# tls-ciphers DEFAULT:!MEDIUM
<% unless @sentinel['tls_ciphers'].nil? %>
tls-ciphers <%= @sentinel['tls_ciphers'] %>
<% end %>

# Configure allowed TLSv1.3 ciphersuites.  See the ciphers(1ssl) manpage for more
# information about the syntax of this string, and specifically for TLSv1.3
# ciphersuites.
#
# tls-ciphersuites TLS_CHACHA20_POLY1305_SHA256
<% unless @sentinel['tls_ciphersuites'].nil? %>
tls-ciphersuites <%= @sentinel['tls_ciphersuites'] %>
<% end %>

# When choosing a cipher, use the server's preference instead of the client
# preference. By default, the server follows the client's preference.
#
# tls-prefer-server-ciphers yes
<% unless @sentinel['tls_prefer_server_ciphers'].nil? %>
tls-prefer-server-ciphers <%= @sentinel['tls_prefer_server_ciphers'] %>
<% end %>

# By default, TLS session caching is enabled to allow faster and less expensive
# reconnections by clients that support it. Use the following directive to disable
# caching.
#
# tls-session-caching no
<% unless @sentinel['tls_session_caching'].nil? %>
tls-session-caching <%= @sentinel['tls_session_caching'] %>
<% end %>

# Change the default number of TLS sessions cached. A zero value sets the cache
# to unlimited size. The default size is 20480.
#
# tls-session-cache-size 5000
<% unless @sentinel['tls_session_cache_size'].nil? %>
tls-session-cache-size <%= @sentinel['tls_session_cache_size'] %>
<% end %>

# Change the default timeout of cached TLS sessions. The default timeout is 300
# seconds.
#
# tls-session-cache-timeout 60
<% unless @sentinel['tls_session_cache_timeout'].nil? %>
tls-session-cache-timeout <%= @sentinel['tls_session_cache_timeout'] %>
<% end %>
<% end %>

# HOSTNAMES SUPPORT
#
# Normally Sentinel uses only IP addresses and requires SENTINEL MONITOR
# to specify an IP address. Also, it requires the Redis replica-announce-ip
# keyword to specify only IP addresses.
#
# You may enable hostnames support by enabling resolve-hostnames. Note
# that you must make sure your DNS is configured properly and that DNS
# resolution does not introduce very long delays.
#
SENTINEL resolve-hostnames <%= @sentinel['use_hostnames'] %>

# When resolve-hostnames is enabled, Sentinel still uses IP addresses
# when exposing instances to users, configuration files, etc. If you want
# to retain the hostnames when announced, enable announce-hostnames below.
#
SENTINEL announce-hostnames <%= @sentinel['use_hostnames'] %>