Sometimes you’ll have to grant other people (or entities) access to your Kubernetes cluster. Easiest is you can give them your admin credentials, but this is similar to giving your house key to a friend, when they only need access to your living room. You can give them different keys, depending on access level required. Those could be readonly access to view services status, or deploy service account that can create/update services. ...
In certain cases, you can’t do a full postgres replication to another instance, or you prefer a fine-grained control on what to replicate, pglogical is one way to achieve partial replication, albeit this requires more manual setup. Below are steps I used to do a pglogical replication from AWS RDS to on-premise database. Note: If a subscriber (from the above example, the on-premise database) is offline, postgres WAL would balloon up. You’ll have to remove all traces of pglogical extension, including uninstalling pglogical extension, then reinitialize everything again to resolve the problem. ...
Successfully deploying services are not the end, maintenance is coming to town! When you want to see how your system works, usually people rely on SaaS like Datadog or New Relic to do the heavy lifting. Also a lot of $$$ is required. Also with SaaS like these, usually you have to config your application to forward metrics/logs to your monitoring provider, this could mean a few months of engineering man-days. ...
Imagine having multiple services running, each has its own logs. Most people don’t read them, and they shouldn’t, because services emit a lot of logs! But we need them, because it’s the only way to diagnose and troubleshoot system errors. But you might say “my service is not a system! It’s only doing tiny stuff!” Gotta break it to you, your small part is a piece in a large system networks stitched together! So your seemingly-tiny service is also important! ...
Kubernetes is awesome, I think this is obvious if you have more than a handful of services to manage. If you use cloud, either VM or container-based runtime, it would provide you a dashboard to see the metrics. But what about kubernetes? Since you would have multiple services inside a single cluster, in which it’s backed by VMs, at best you would only see into your VMs’ metrics, but doesn’t provide separate metrics per each service. ...