diff --git a/src/go/mongolib/proto/replconfig.go b/src/go/mongolib/proto/replconfig.go
new file mode 100644
index 00000000..8ce984d2
--- /dev/null
+++ b/src/go/mongolib/proto/replconfig.go
@@ -0,0 +1,50 @@
+package proto
+
+import (
+	"gopkg.in/mgo.v2/bson"
+)
+
+type ReplicaSetConfigTags map[string]string
+type GetLastErrorModes map[string]*ReplicaSetConfigTags
+
+// https://docs.mongodb.com/v3.2/reference/command/getLastError/#dbcmd.getLastError
+type GetLastErrorDefaults struct {
+	Journal      bool  `bson:"j,omitempty"`        // If true, wait for the next journal commit before returning, rather than waiting for a full disk flush.
+	WriteConcern int64 `bson:"w,omitempty"`        // When running with replication, this is the number of servers to replicate to before returning.
+	WTimeout     int64 `bson:"wtimeout,omitempty"` // Optional. Milliseconds. Specify a value in milliseconds to control how long to wait for write propagation to complete.
+}
+
+// https://docs.mongodb.com/v3.2/reference/replica-configuration/#rsconf.members
+type ReplicaSetConfigMember struct {
+	ID           int64                 `bson:"_id,omitempty"`          // An integer identifier of every member in the replica set.
+	Host         string                `bson:"host,omitempty"`         // The hostname and, if specified, the port number, of the set member.
+	ArbiterOnly  bool                  `bson:"arbiterOnly,omitempty"`  // A boolean that identifies an arbiter. A value of true indicates that the member is an arbiter.
+	BuildIndexes bool                  `bson:"buildIndexes,omitempty"` // A boolean that indicates whether the mongod builds indexes on this member.
+	Hidden       bool                  `bson:"hidden,omitempty"`       // When this value is true, the replica set hides this instance and does not include the member in the output of db.isMaster() or isMaster.
+	Priority     int64                 `bson:"priority,omitempty"`     // A number that indicates the relative eligibility of a member to become a primary.
+	Tags         *ReplicaSetConfigTags `bson:"tags,omitempty"`         // A tag set document containing mappings of arbitrary keys and values.
+	SlaveDelay   int64                 `bson:"slaveDelay,omitempty"`   // The number of seconds “behind” the primary that this replica set member should “lag”.
+	Votes        int64                 `bson:"votes,omitempty"`        // The number of votes a server will cast in a replica set election.
+}
+
+// https://docs.mongodb.com/v3.2/reference/replica-configuration/#rsconf.settings
+type ReplicaSetConfigSettings struct {
+	ChainingAllowed         bool                  `bson:"chainingAllowed,omitempty"`         // When chainingAllowed is true, the replica set allows secondary members to replicate from other secondary members.
+	HeartbeatTimeoutSecs    int64                 `bson:"heartbeatTimeoutSecs,omitempty"`    // Number of seconds that the replica set members wait for a successful heartbeat from each other.
+	HeartbeatIntervalMillis int64                 `bson:"heartbeatIntervalMillis,omitempty"` // The frequency in milliseconds of the heartbeats.
+	ElectionTimeoutMillis   int64                 `bson:"electionTimeoutMillis,omitempty"`   // The time limit in milliseconds for detecting when a replica set’s primary is unreachable.
+	GetLastErrorDefaults    *GetLastErrorDefaults `bson:"getLastErrorDefaults,omitempty"`    // A document that specifies the write concern for the replica set.
+	GetLastErrorModes       *GetLastErrorModes    `bson:"getLastErrorModes,omitempty"`       // A document used to define an extended write concern through the use of members[n].tags.
+	ReplicaSetId            *bson.ObjectId        `bson:"replicaSetId,omitempty"`            // Replset Id (ObjectId)
+}
+
+type ReplicaSetConfig struct {
+	Config struct {
+		ID              string                    `bson:"_id,omitempty"`             // The name of the replica set. Once set, you cannot change the name of a replica set.
+		ProtocolVersion int64                     `bson:"protocolVersion,omitempty"` // By default, new replica sets in MongoDB 3.2 use protocolVersion: 1. Previous versions of MongoDB use version 0.
+		Version         int64                     `bson:"version,omitempty"`         // An incrementing number used to distinguish revisions of the replica set configuration object from previous iterations.
+		Members         []*ReplicaSetConfigMember `bson:"members,omitempty"`         // An array of member configuration documents, one for each member of the replica set.
+		Settings        *ReplicaSetConfigSettings `bson:"settings,omitempty"`        // A document that contains configuration options that apply to the whole replica set.
+	} `bson:"config,omitempty"` // https://docs.mongodb.com/v3.2/reference/replica-configuration/#replica-set-configuration-fields
+	Ok int64 `bson:"ok,omitempty"`
+}