Hello,
I read at Replica Set Arbiter - Database Manual v8.0 - MongoDB Docs, the following
Warning
Using a architecture for shards in a sharded cluster can cause a loss of availability if a data-bearing secondary is unavailable. A PSA cluster differs from a typical replica set: In a sharded cluster, shards perform w: majority that cannot complete if the remaining cluster members required to confirm an operation have an arbiter.
I don’t understand why sharding make any difference to write concerns. Sharding or not, if the secondary is down, it won’t be possible to have the majority during a write (because only the primary can write data). So, in any case, the wring concerns will not complete.
What am I missing ?
Regards,