Configuring JetStream

Configuring JetStream
Enabling JetStream for a nats-server
To enable JetStream in a server we have to configure it at the top level first:
jetstream: enabled
You can also use the -js, --jetstream and -sd, --store_dir <dir> flags from the command line
Multi-tenancy & Resource Mgmt
JetStream is compatible with NATS 2.0 Multi-Tenancy using Accounts. A JetStream enabled server supports creating fully isolated JetStream environments for different accounts.
This will dynamically determine the available resources. It's recommended that you set specific limits though:
jetstream {
    store_dir: /data/jetstream
    max_mem: 1G
    max_file: 100G
}
Setting account resource limits
At this point JetStream will be enabled and if you have a server that does not have accounts enabled, all users in the server would have access to JetStream
jetstream {
    store_dir: /data/jetstream
    max_mem: 1G
    max_file: 100G
}
​
accounts {
    HR: {
        jetstream: enabled
    }
}
Here the HR account would have access to all the resources configured on the server, we can restrict it:
jetstream {
    store_dir: /data/jetstream
    max_mem: 1G
    max_file: 100G
}
​
accounts {
    HR: {
        jetstream {
            max_mem: 512M
            max_file: 1G
            max_streams: 10
            max_consumers: 100
        }
    }
}
Now the HR account is limited in various dimensions.
If you try to configure JetStream for an account without enabling it globally you'll get a warning and the account designated as System cannot have JetStream enabled.
Operator mode account resources limits using the nsc CLI tool
If your setup is in operator mode, JetStream specific account configuration can be stored in account JWT. The earlier account named HR can be configured as follows:
nsc add account --name HR
nsc edit account --name HR --js-mem-storage 1G --js-disk-storage 512M  --js-streams 10 --js-consumer 100

Last modified 1yr ago