Host Properties (nuoadmin.conf)
To configure a host, set the required values for properties in nuoadmin.conf.
You can find nuoadmin.conf in the following locations:
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RPM |
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TAR |
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Windows MSI |
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Setting nuoadmin.conf Properties
Using a text editor, define Admin Process (AP) settings using nuoadmin.conf properties.
Some of the nuoadmin.conf properties are described in the below table.
All properties are described in the configuration file shipped with the product or in the sample configuration file located at $NUODB_HOME/etc/nuoadmin.conf.sample.
| Property | Description | Comments | ||
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A map of servers and details for APs that are allowed to create/bootstrap the domain.
Each key is a server ID, with values such as that seen in Example 1 below.
If one of the keys matches the value of |
The associated transport property is a host name or IP address and port number following the format For more information, see Notes on Setting the peer and initialMembership Properties.
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An endpoint (host:port) through which new admin servers can join the membership. This can be the address of a specific admin server in the membership, or a load-balancer that is routing traffic to existing admin servers. |
For more information, see Notes on Setting the peer and initialMembership Properties. |
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A unique identifier for this AP that is permanently assigned, for example |
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The address which the AP stores in the Raft membership, and the address that all other APs use to communicate with it. If it is not specified, an AP stores its hostname in the durable membership (which other APs can then use to communicate with it). |
When set, the value for
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The port used by SQL clients to obtain a connection from an AP and also used by database processes to communicate with an AP. |
Default is |
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The port that APs use to communicate with each other. |
Default is |
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The port used by the REST API service.
If |
Default is |
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Default log level for the root logger, which is inherited by all other loggers that do not have log levels defined using |
Default is |
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Log levels for not-root loggers, specified as a mapping of logger name, or prefix of logger name, to log level.
For example, |
Default is |
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Used to enable or disable logging to standard output.
This must be set to |
Default is |
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Log levels for standard output logging.
This is specified in the same way |
Default is |
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The port range that database processes managed by the AP should listen on.
A database process on a host will scan the port range until it finds a port that it can listen on.
Can be an bounded range such as |
Default value is |
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Used to enable or disable SSL (TLS) domain connection and membership authentication. |
Default value is |
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If set to a non-empty value, the AP enforces hostname matching during the certificate verification process to restrict access to clients with non-root certificates. This process allows a public CA to be used as a trusted root without giving access to all clients with certificates signed by the same CA.
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Default value is the empty string ( |
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The maximum amount of time (in seconds) for a new AP to wait to join the domain. |
Default is |
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The maximum amount of time (in milliseconds) to wait for all initialized archives to be started when assigning storage group leaders for a database. |
Default is |
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The maximum amount of time (in milliseconds) to wait for a database process to connect to the AP after it is started. |
Default is |
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The maximum amount of time (in milliseconds) to wait for a database process to reconnect to the AP after the AP is restarted. |
Default is |
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Whether to force unknown database processes attempting to reconnect to the AP to shutdown.
Note that this implies that the process either does not exist at all in the current domain (e.g. the domain was reprovisioned from scratch but the process was left running from the previous domain), or was explicitly removed from the domain state (e.g. using |
Default is |
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The maximum period of time (in microseconds) it would take the Raft leader to send a heartbeat to all followers; the heartbeat period and election timeout range are both calculated as multiples of the |
When working with large clusters (20 or more APs), or high-latency environments, consider increasing the value set for this property. The value set for ( |
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Garbage collection of exited database processes (tombstones) prevents the domain state from growing too large.
Garbage collection is performed periodically every |
Default is |
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Defines the number of tombstones at which garbage collection is triggered. |
Default is |
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Defines the minimum number of tombstones to retain and should be lower than |
Default is |
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Defines the number of database incarnations to retain when garbage collecting tombstones for processes that were gracefully shutdown.
Processes that were gracefully shutdown more than |
Default is |
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If the Admin is TLS-enabled and has a certificate with signing rights (i.e. the certificate has the attribute |
Default is |
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The strength of the generated key, which corresponds to a particular size in bits for each algorithm.
The key strengths are |
Default is |
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The NuoDB license file location.
A license file at the supplied path will be loaded if no other license has been installed using |
Default is |
Notes on Setting the peer and initialMembership Properties
Physical and VMware deployments
So there is no restriction to the endpoints that a new server can join through, the peer property can be set to a load-balancer in front of the admin servers currently running.
However, when setting peer, a disadvantage is that there is a race condition on who the initial member is, which could lead to different servers bootstrapping different domains.
This is solved by setting both peer and initialMembership.
If the domain has not been bootstrapped yet, then it can only be bootstrapped by a majority of the servers displayed in initialMembership.
If a server is not displayed in initialMembership, then it must join through the peer endpoint.
For NuoDB Admin step by step configuration guidelines, see Configuring NuoDB Admin.
Containerized Deployments
In containerized environments, the container entrypoint script to start the AP injects values into nuoadmin.conf based on environment variables.
The NUODB_DOMAIN_ENTRYPOINT variable becomes the peer and the NUODB_BOOTSTRAP_SERVERID variable becomes the lone member in the initial membership.
For more information, see Admin Process (AP).
Example 1
The following nuoadmin.conf code sample provides settings for an admin service defined on host server0 that is also the initial member:
...
"initialMembership": {
"server0" : { "transport" : "server0:48005", "version" : "0:10000" }
},
"ThisServerId": "server0",
"altAddr": "server0",
"adminPort": "48005",
...
As this is the first host, the value of ThisServerId appears in the initialMembership.
The altAddr property is the address that is advertised by a particular AP.
The default value of altAddr is $(hostname), which expands to the hostname of the server.
The ThisServerId property is a user-defined unique identifier for an AP, and is typically chosen to match the altAddr, assuming that all hosts have stable and unique hostnames.
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Once the domain has been bootstrapped (service started), you can’t change the value for initialMembership.
In the event that you need to change this value, you must shutdown the nuoadmin service and remove the raftlog file for all APs in the domain (located in /var/opt/nuodb by default).
This would result in the loss of any configuration data in the domain, including all database and archive metadata (the archive data itself is unaffected) and SQL load balancer configuration.
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Example 2
The use of the peer property enables late binding of the initial membership.
peer and initialMembership are only used if there is no durable Raft state.
If there is durable Raft state, the membership from the recovered Raft state is used.
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The peer property specifies an address (host and port) to query for the initial membership to use when entering the domain.
Unlike the addresses in the initial membership, there is no requirement that the address specified by peer actually belongs to a server in the membership, which means that it could actually be the address of a load balancer (for example Nginx or an Elastic Load Balancer) that is brokering the existing set of admin servers.
...
"peer": "server0",
"ThisServerId" : "server0",
"altAddr" : "server0",
...Expansion of Files and Variables
It is possible to specify configuration properties in nuoadmin.conf that are not bound until the AP is started.
The syntax ${VAR} can be used evaluate a JVM property or an environment variable. For example, the following entry can be used to specify the password used to protect an AP’s keystore:
...
"keystore-password": "${NUODB_KEYSTORE_PASSWORD}",
...This will evaluate to the JVM property NUODB_KEYSTORE_PASSWORD or the environment variable NUODB_KEYSTORE_PASSWORD.
JVM properties take precedence over environment variables.
It is also possible to expand the contents of a file as a configuration property, using the syntax $(</path/to/file).
For example, the following entry can be used to specify the password used to protect an AP’s keystore:
...
"keystore-password": "$(</etc/nuodb/keys/keystore-password)",
...This will expand the contents of /etc/nuodb/keys/keystore-password, removing any leading or trailing whitespace.
| Variable and file expansion can be performed for the value of a key-value entry, but not the key. In other words, these expressions can only appear on right-hand side of a key-value entry. |