ArangoDB cluster
Datacenter to datacenter replication requires the storage engine. Theexample setup described in this section will have rocksdb
enabled. If you chooseto deploy with a different strategy keep in mind to set the storage engine.
For other possibilities to deploy an ArangoDB cluster see.
The Starter simplifies things for the operator and will coordinate a distributedcluster startup across several machines and assign cluster roles automatically.
When started on several machines and enough machines have joined, the Starters_will start _Agents, Coordinators and DBservers on these machines.
To start the cluster using a systemd
unit file use the following:
Note that we set in the unit service file.
The communication between the cluster nodes use a token (JWT) to authenticate.This must be shared between cluster nodes.
Sharing secrets is obviously a very delicate topic. The above workflow assumesthat the operator will put a secret in a file named ${CLUSTERSECRETPATH}
.
As soon as enough machines have joined, the Starter will begin starting Agents,Coordinators and DBservers.
Each of these tasks needs a port to communicate. Please make sure that the followingports are available on all machines:
8530
for DB-Servers
The Starter itself will use port .
Since the Agents are so critical to the availability of both the ArangoDB and the ArangoSync cluster,it is recommended to run Agents on dedicated machines. Consider these machines “pets”.