}, "name" : "quote_text_translation.quote_text", "ns" : "test.quotes", "weights" : { "quote" : 1, "translation.quote" : 1 }, "default_language" : "english", "language_override" : "language", "textIndexVersion" : 2 } 2dsphere Index Version Check If you have version 2 2dsphere indexes (i.e. the default version for 2dsphere indexes in MongoDB 2.6), drop the version 2 2dsphere indexes before downgrading MongoDB. After the down- grade, recreate the 2dsphere indexes. To determine the version of your 2dsphere indexes, run db.collection.getIndexes() to view index specifications. For 2dsphere indexes, the method returns the version information in the field 2dsphereIndexVersion . For example, the following shows that the 2dsphere index on the locations collection is version 2. Downgrade 2.6 Standalone mongod Instance The following steps outline the procedure to downgrade a stan- dalone mongod from version 2.6 to 2.4. Downgrade a 2.6 Replica Set The following steps outline a “rolling” downgrade process for the replica set. The “rolling” downgrade process minimizes downtime by downgrading the members individually while the other members are available: Replace and restart secondary mongod instances. First, shut down the mongod , then replace these binaries with the 2.4 binary and restart mongod . See Stop mongod Processes (page 225) for instructions on safely terminating mongod processes. Step 1: Downgrade each secondary member, one at a time. For each secondary in a replica set: 875 12.2. Previous Stable Releases { "v" : 1, "key" : { "geo" : "2dsphere" }, "name" : "geo_2dsphere", "ns" : "test.locations", "sparse" : true , "2dsphereIndexVersion" : 2 } Downgrade MongoDB Processes 1. Download binaries of the latest release in the 2.4 series from the MongoDB Download Page$^{675}$. See Install MongoDB (page 5) for more information. 2. Shut down your mongod instance. Replace the existing binary with the 2.4 mongod binary and restart mongod . $^{675}$http://www.mongodb.org/downloads MongoDB Documentation, Release 3.0.4