Mongo DB recommends all update() operations for a sharded collection that specify the signle document update only ‘multi:false’ option (which is by default) must include the shard key in the query condition so the query will hit only a specific shard cluster. If no shard key found and ‘multi:false’, it returns this error (See http://docs.mongodb.org/manual/core/sharded-cluster-query-router/)

In version 2.4, the error message is ‘for non-multi updates must have _id or full shard key’

Error occurs when creating a ‘text’ index in Mongo to enable text search on a field, e.g., db.collection.ensureIndex( { fieldname: “text” }),  but textSearchEnabled is not enable in mongod. Try to run mongod with textSearchEnable=true

mongod –setParameter textSearchEnabled=true

or add textSearchEnabled=true in mongod.conf

The sort() method only accepts 1 or -1. Other values like true or false, null… will return this error “BadValue bad sort specification”.

.sort({“field”: 1})
.sort({“field1″: 1, “field2″: -1})

Reference: http://docs.mongodb.org/manual/reference/method/cursor.sort/#cursor.sort

You are using a new mongo (>= 2.6) shell to connect a older version mongod (2.4). The new mongo shell now integrates the write concern directly into the method (insert, update) rather than with a separate getLastError command, which is not supported by older mongod. The new shell then decide to downgrade to be compatible.

Solution: You can simply ignore this warning or try to use the correct mongo shell version.

Command db.setProfilingLevel() cannnot be used with sharded mongos.

However we can use db.setProfilingLevel() against any shard cluster mongod if needed