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axon-server installation (CentOS / RedHat)

Step 1 - Prerequisites

Elasticsearch stores the data collected by axon-server. AxonOps is currently only compatible with Elasticsearch 7.x, we recommend installing the latest available 7.x release.

Installing Elasticsearch

wget https://artifacts.elastic.co/downloads/elasticsearch/elasticsearch-7.17.16-x86_64.rpm
wget https://artifacts.elastic.co/downloads/elasticsearch/elasticsearch-7.17.16-x86_64.rpm.sha512
sha512sum -c elasticsearch-7.17.16-x86_64.rpm.sha512
sudo rpm -i elasticsearch-7.17.16-x86_64.rpm

The sha512sum command above verifies the downloaded package and should show this output: 

elasticsearch-7.17.16-x86_64.rpm: OK

Increase the bulk queue size of Elasticsearch by running the following command:

sudo echo 'thread_pool.write.queue_size: 2000' >> /etc/elasticsearch/elasticsearch.yml

Increase the default heap size of elasticsearch by editing /etc/elasticsearch/jvm.options.

Set Xmx and Xms to no more than 50% of your physical RAM.

Example:

From: 

-Xms1g
-Xmx1g
To: 
-Xms8g
-Xmx8g
This will set the minimum and maximum heap size to 8 GB.

Elasticsearch requires memory for purposes other than the JVM heap and it is important to leave available memory(RAM) space for this.

Set the following index codec by running the following command:

sudo echo 'index.codec: best_compression' >> /etc/elasticsearch/elasticsearch.yml

Elasticsearch uses an mmapfs directory by default to store its indices.

The default operating system limits on mmap counts is likely to be too low, which may result in out of memory exceptions.

You can increase the limits by running the following command:

sudo sysctl -w vm.max_map_count=262144

To make this change persist across reboots run this command:

echo "vm.max_map_count = 262144" | sudo tee /etc/sysctl.d/10-elasticsearch.conf > /dev/null

Elasticsearch needs max file descriptors system settings at least to 65536.

echo 'elasticsearch  -  nofile  65536' | sudo tee --append /etc/security/limits.conf > /dev/null

Start Elasticsearch

sudo systemctl start elasticsearch.service

After a short period of time, you can verify that your Elasticsearch node is running by sending an HTTP request to port 9200 on localhost:

curl "localhost:9200"

Securing Elasticsearch

Securing Elasticsearch

Step 2 - axon-server

sudo tee /etc/yum.repos.d/axonops-yum.repo << EOL
[axonops-yum]
name=axonops-yum
baseurl=https://packages.axonops.com/yum/
enabled=1
repo_gpgcheck=0
gpgcheck=0
EOL

sudo yum install axon-server

Step 3 - axon-server configurations

Make sure elastic_host and elastic_port are corresponding to your Elasticsearch instance.

Basic Auth in Elasticsearch

  • Create a user that has a dedicated role and username password.
  • Please dont use any of the built in users for Elasticsearch.

To create users please refer to the Elasticsearch docs here

AxonOps Server configuration file location : /etc/axonops/axon-server.yml

host: 0.0.0.0  # axon-server listening address (used by axon-agents for connections) (env variable: AXONSERVER_HOST)
agents_port: 1888 # axon-server listening port for agent connections 

api_host: 127.0.0.1 # axon-server listening address (used by axon-dash for connections)
api_port: 8080 # axon-server HTTP API listening port (used by axon-dash) (AXONSERVER_PORT)

elastic_hosts: # Elasticsearch endpoint (env variable:ELASTIC_HOSTS, comma separated list)
  - http://localhost:9200
# SSL/TLS config for Elasticsearch
# elastic_hosts:
# - https://username:[email protected]
# - https://username:[email protected]
# - https://username:[email protected]
# elastic_skipVerify: true # Disables CA and Hostname verification

# Used by Axon-Server to auto discover Elasticsearch nodes in a cluster.
# Allows more nodes to be added to Elasticsearch for Metrics storage without having to restart Axon-Server and update elastic_hosts with all the ELK node values.
# elastic_discover_nodes: true # Default = true

#integrations_proxy: # proxy endpoint for integrations. (INTEGRATIONS_PROXY)

# AxonOps licensing
license_key: license-key
org_name: my-company

# SSL/TLS Settings for AxonOps Agent connections
tls:
  mode: "disabled" # disabled, TLS
  # Only set if mode is TLS
  skipVerify: false # Disables CA and Hostname verification
  caFile: "path_to_certs_on_axonops_server.crt"
  certFile: "path_to_certs_on_axonops_server.crt"
  keyFile: "path_to_key_file_on_axonops_server.key"

# For better performance on large clusters, you can use a CQL store for the metrics.
# To opt-in for CQL metrics storage, just specify at least one CQL host.
# We do recommend to specify a NetworkTopologyStrategy for cql_keyspace_replication
#cql_hosts: #  (CQL_HOSTS, comma separated list)
#  - 192.168.0.10:9042
#  - 192.168.0.11:9042
#cql_username: "cassandra" # (CQL_USERNAME)
#cql_password: "cassandra" # (CQL_PASSWORD)
#cql_local_dc: datacenter1 # (CQL_LOCAL_DC)
#cql_ssl: false # (CQL_SSL)
#cql_skip_verify: false  # (CQL_SSL_SKIP_VERIFY)
#cql_ca_file: /path/to/ca_file  # (CQL_CA_FILE)
#cql_cert_file: /path/to/cert_file  # (CQL_CERT_FILE)
#cql_key_file: /path/to/key_file  # (CQL_KEY_FILE)
#cql_proto_version: 4  # (CQL_PROTO_VERSION)
#cql_max_concurrent_reads: 1000  # (CQL_MAX_CONCURRENT_READS)
#cql_batch_size: 1  # (CQL_BATCH_SIZE)
#cql_page_size: 10  # (CQL_PAGE_SIZE)
#cql_autocreate_tables: true # (CQL_AUTO_CREATE_TABLES) this will tell axon-server to automatically create the metrics tables (true is recommended)
#cql_keyspace_replication: "{ 'class' : 'SimpleStrategy', 'replication_factor' : 1 }" # (CQL_KS_REPLICATION) keyspace replication for the metrics tables
#cql_retrypolicy_numretries: 3  # (CQL_RETRY_POLICY_NUM_RETRIES)
#cql_retrypolicy_min: 1s  # (CQL_RETRY_POLICY_MIN)
#cql_retrypolicy_max: 10s  # (CQL_RETRY_POLICY_MAX)
#cql_reconnectionpolicy_maxretries: 10 # (CQL_RECONNECTION_POLICY_MAX_RETRIES)
#cql_reconnectionpolicy_initialinterval: 1s # (CQL_RECONNECTION_POLICY_INITIAL_INTERVAL)
#cql_reconnectionpolicy_maxinterval: 10s # (CQL_RECONNECTION_POLICY_MAX_INTERVAL)
#cql_metrics_cache_max_size_mb: 100  #MB # (CQL_METRICS_CACHE_MAX_SIZE_MB)
#cql_read_consistency: "LOCAL_ONE" # (CQL_READ_CONSISTENCY) #One of the following:  ANY, ONE, TWO, THREE, QUORUM, ALL, LOCAL_QUORUM, EACH_QUORUM, LOCAL_ONE
#cql_write_consistency: "LOCAL_ONE" # (CQL_WRITE_CONSISTENCY) #One of the following:    ANY, ONE, TWO, THREE, QUORUM, ALL, LOCAL_QUORUM, EACH_QUORUM, LOCAL_ONE
#cql_lvl1_compaction_window_size: 12 # (CQL_LVL1_COMPACTION_WINDOW_SIZE)
#cql_lvl2_compaction_window_size: 1 # (CQL_LVL2_COMPACTION_WINDOW_SIZE)
#cql_lvl3_compaction_window_size: 1 # (CQL_LVL3_COMPACTION_WINDOW_SIZE)
#cql_lvl4_compaction_window_size: 10 # (CQL_LVL4_COMPACTION_WINDOW_SIZE)
#cql_lvl5_compaction_window_size: 120 # (CQL_LVL5_COMPACTION_WINDOW_SIZE)

axon-dash: # This must point to the axon-dash address accessible from axon-server
  host: 127.0.0.1
  port: 3000
  https: false

alerting:
# How long to wait before sending a notification again if it has already
# been sent successfully for an alert. (Usually ~3h or more).
  notification_interval: 3h

# Default retention settings, most can be overridden from the frontend
retention:
  events: 8w # logs and events retention. Must be expressed in weeks (w)
  metrics:
      high_resolution: 14d # High frequency metrics. Must be expressed in days (d)
      med_resolution: 12w # Must be expressed in weeks (w)
      low_resolution: 12M # Must be expressed in months (M)
      super_low_resolution: 2y # Must be expressed in years (y)
  backups: # Those are use as defaults but can be overridden from the UI
    local: 10d
    remote: 30d


# Storage options for PDF reports
# Override the default local path of /var/lib/axonops/reports
#report_storage_path: /my/reports/storage/directory

# Alternatively store PDF reports in an object store by providing report_storage_config
#report_storage_path: my-reports-s3-bucket/reports-folder
#report_storage_config:
#  type: s3
#  provider: AWS
#  access_key_id: MY_ACCESS_KEY_ID
#  secret_access_key: MY_SECRET_ACCESS_KEY
#  region: us-east-1
#  acl: private
#  server_side_encryption: AES256
#  storage_class: STANDARD

For better performances on large clusters (100+ nodes), you can use a CQL store for the metrics such as Cassandra. To opt-in for CQL metrics storage, specify at least one CQL host with axon-server configuration.

Step 4 - Start the server

sudo systemctl daemon-reload
sudo systemctl start axon-server
sudo systemctl status axon-server

This will start the axon-server process as the axonops user, which was created during the package installation. The default listening address is 0.0.0.0:8080.

Package details

  • Configuration: /etc/axonops/axon-server.yml
  • Binary: /usr/share/axonops/axon-server
  • Logs: /var/log/axonops/axon-server.log
  • Systemd service: /usr/lib/systemd/system/axon-server.service
  • Copyright : /usr/share/doc/axonops/axon-server/copyright
  • Licenses : /usr/share/axonops/licenses/axon-server/

Step 5 - Installing axon-dash

Now axon-server is installed, you can start installing the GUI for it: axon-dash