<p>I want to deploy MongoDB to Kubernetes cluster with 2 nodes, there is no chance to add another node in the future.</p>
<p>I want to deploy MongoDB as standalone because both node will be able to access to same disk space via NFS and I don't have requirements for replication or high availability. However, in the MongoDB docs, it is clearly stated that standalone deployment is not suitable for production environment.</p>
<p><a href="https://docs.cloudmanager.mongodb.com/tutorial/deploy-standalone/" rel="nofollow noreferrer">MongoDB Deploy Standalone</a></p>
<blockquote>
<p>You can deploy a standalone MongoDB instance for Cloud Manager to manage. Use standalone instances for testing and development. Do not use these deployments for production systems as they lack replication and high availability.</p>
</blockquote>
<p>What kind of drawbacks I can face? Should I deploy as replica set with arbiter instance? If yes, why?</p>

Seyfullah Yamanoğlu
<p>Of course you can deploy a Standalone MongoDB for production. But if this node fails, then your application is not available anymore. If you don't have any requirement for availability then go for a Standalone MongoDB.</p>
<p>However, running 2 MongoDB services which access the same physical disk (i.e. <code>dbPath</code>) will not work. Each MongoDB instance need to have a dedicated data folder.</p>
<p>In your case, I would suggest a <a href="https://docs.mongodb.com/manual/tutorial/deploy-replica-set/" rel="nofollow noreferrer">Replica Set</a>. All data from one node will be replicated to the other one. If one node fails then the application goes into &quot;read/only&quot; mode.</p>
<p>You can deploy an arbiter instance on the primary node. If the secondary node goes down, then the application is still fully available.</p>
