6 node no range merge

*
* WARNING: RUNNING IN INSECURE MODE!
* 
* - Your cluster is open for any client that can access <all your IP addresses>.
* - Any user, even root, can log in without providing a password.
* - Any user, connecting as root, can read or write any data in your cluster.
* - There is no network encryption nor authentication, and thus no confidentiality.
* 
* Check out how to secure your cluster: https://www.cockroachlabs.com/docs/v2.2/secure-a-cluster.html
*
*
* WARNING: neither --listen-addr nor --advertise-addr was specified.
* The server will advertise "ip-172-31-41-232" to other nodes, is this routable?
* 
* Consider using:
* - for local-only servers:  --listen-addr=localhost
* - for multi-node clusters: --advertise-addr=<host/IP addr>
* 
*
*
* ERROR: [n5,client=172.31.42.127:50898,user=root,txn=44987ebc] a panic has occurred!
*
runtime error: index out of range

goroutine 85385605 [running]:
runtime/debug.Stack(0x38b4fc0, 0xc0b35998c0, 0xc000000003)
	/usr/local/go/src/runtime/debug/stack.go:24 +0xa7
github.com/cockroachdb/cockroach/pkg/util/log.ReportPanic(0x38b4fc0, 0xc0b35998c0, 0xc000493300, 0x2d24ec0, 0x5486fa0, 0x1)
	/go/src/github.com/cockroachdb/cockroach/pkg/util/log/crash_reporting.go:212 +0xa6
github.com/cockroachdb/cockroach/pkg/util/stop.(*Stopper).Recover(0xc0001fd560, 0x38b4fc0, 0xc0b35998c0)
	/go/src/github.com/cockroachdb/cockroach/pkg/util/stop/stopper.go:181 +0xe4
panic(0x2d24ec0, 0x5486fa0)
	/usr/local/go/src/runtime/panic.go:513 +0x1b9
github.com/cockroachdb/cockroach/pkg/roachpb.(*ScanRequest).MarshalTo(0xc08bb7ba80, 0xc014e5a284, 0x15, 0x15, 0x17, 0x2, 0x13)
	/go/src/github.com/cockroachdb/cockroach/pkg/roachpb/api.pb.go:10150 +0x17d
github.com/cockroachdb/cockroach/pkg/roachpb.(*RequestUnion_Scan).MarshalTo(0xc02dc4c970, 0xc014e5a282, 0x17, 0x17, 0xf2b11e, 0xc02dc4c970, 0x19)
	/go/src/github.com/cockroachdb/cockroach/pkg/roachpb/api.pb.go:13237 +0xdf
github.com/cockroachdb/cockroach/pkg/roachpb.(*RequestUnion).MarshalTo(0xc07f36e848, 0xc014e5a282, 0x17, 0x17, 0x19, 0xc2, 0x0)
	/go/src/github.com/cockroachdb/cockroach/pkg/roachpb/api.pb.go:13138 +0x73
github.com/cockroachdb/cockroach/pkg/roachpb.(*BatchRequest).MarshalTo(0xc07e204480, 0xc014e5a1c0, 0xd9, 0xd9, 0xd9, 0xd9, 0x30c6000)
	/go/src/github.com/cockroachdb/cockroach/pkg/roachpb/api.pb.go:14550 +0x246
github.com/cockroachdb/cockroach/pkg/roachpb.(*BatchRequest).Marshal(0xc07e204480, 0x30c6000, 0xc07e204480, 0x7f67672ed208, 0xc07e204480, 0xc03a33b701)
	/go/src/github.com/cockroachdb/cockroach/pkg/roachpb/api.pb.go:14525 +0x7f
github.com/cockroachdb/cockroach/vendor/google.golang.org/grpc/encoding/proto.codec.Marshal(0x30c6000, 0xc07e204480, 0xc03b3134a0, 0x3, 0xc00006c570, 0xc00006c500, 0x7f676c175f40)
	/go/src/github.com/cockroachdb/cockroach/vendor/google.golang.org/grpc/encoding/proto/proto.go:70 +0x19c
github.com/cockroachdb/cockroach/vendor/google.golang.org/grpc.encode(0x7f676b425490, 0x5912dd8, 0x30c6000, 0xc07e204480, 0xc0393a6f30, 0x38e00c0, 0x38b5d00, 0x500000005, 0x0)
	/go/src/github.com/cockroachdb/cockroach/vendor/google.golang.org/grpc/rpc_util.go:487 +0x5e
github.com/cockroachdb/cockroach/vendor/google.golang.org/grpc.(*csAttempt).sendMsg(0xc01cc59e10, 0x30c6000, 0xc07e204480, 0x0, 0x0)
	/go/src/github.com/cockroachdb/cockroach/vendor/google.golang.org/grpc/stream.go:482 +0xca
github.com/cockroachdb/cockroach/vendor/google.golang.org/grpc.(*clientStream).SendMsg(0xc07e204500, 0x30c6000, 0xc07e204480, 0xc000f52000, 0x313d4c0)
	/go/src/github.com/cockroachdb/cockroach/vendor/google.golang.org/grpc/stream.go:403 +0x43
github.com/cockroachdb/cockroach/vendor/google.golang.org/grpc.invoke(0x38b4fc0, 0xc0b35998c0, 0x313d4c0, 0x21, 0x30c6000, 0xc07e204480, 0x301af40, 0xc0797cf0a0, 0xc000f52000, 0xc00033f720, ...)
	/go/src/github.com/cockroachdb/cockroach/vendor/google.golang.org/grpc/call.go:75 +0xfe
github.com/cockroachdb/cockroach/vendor/github.com/grpc-ecosystem/grpc-opentracing/go/otgrpc.OpenTracingClientInterceptor.func1(0x38b4fc0, 0xc0b35998c0, 0x313d4c0, 0x21, 0x30c6000, 0xc07e204480, 0x301af40, 0xc0797cf0a0, 0xc000f52000, 0x32614c8, ...)
	/go/src/github.com/cockroachdb/cockroach/vendor/github.com/grpc-ecosystem/grpc-opentracing/go/otgrpc/client.go:47 +0xb49
github.com/cockroachdb/cockroach/vendor/google.golang.org/grpc.(*ClientConn).Invoke(0xc000f52000, 0x38b4fc0, 0xc0b35998c0, 0x313d4c0, 0x21, 0x30c6000, 0xc07e204480, 0x301af40, 0xc0797cf0a0, 0x0, ...)
	/go/src/github.com/cockroachdb/cockroach/vendor/google.golang.org/grpc/call.go:35 +0x109
github.com/cockroachdb/cockroach/pkg/roachpb.(*internalClient).Batch(0xc0b41b3918, 0x38b4fc0, 0xc0b35998c0, 0xc07e204480, 0x0, 0x0, 0x0, 0xc0b35998c0, 0x1, 0x38b4fc0)
	/go/src/github.com/cockroachdb/cockroach/pkg/roachpb/api.pb.go:9299 +0xd2
github.com/cockroachdb/cockroach/pkg/kv.(*grpcTransport).sendBatch(0xc0393a6ed0, 0x38b4fc0, 0xc0b35998c0, 0x1, 0x3889000, 0xc0b41b3918, 0x0, 0x0, 0x100000001, 0x1, ...)
	/go/src/github.com/cockroachdb/cockroach/pkg/kv/transport.go:199 +0x126
github.com/cockroachdb/cockroach/pkg/kv.(*grpcTransport).SendNext(0xc0393a6ed0, 0x38b4fc0, 0xc0b35998c0, 0x0, 0x0, 0x100000001, 0x1, 0x418b, 0x0, 0xc011dff200, ...)
	/go/src/github.com/cockroachdb/cockroach/pkg/kv/transport.go:168 +0x130
github.com/cockroachdb/cockroach/pkg/kv.(*DistSender).sendToReplicas(0xc000864100, 0x38b4fc0, 0xc0b35998c0, 0xc000864150, 0x418b, 0xc02c92af50, 0x3, 0x3, 0x0, 0x0, ...)
	/go/src/github.com/cockroachdb/cockroach/pkg/kv/dist_sender.go:1345 +0x2d3
github.com/cockroachdb/cockroach/pkg/kv.(*DistSender).sendRPC(0xc000864100, 0x38b4fc0, 0xc0b35998c0, 0x418b, 0xc02c92af50, 0x3, 0x3, 0x0, 0x0, 0x0, ...)
	/go/src/github.com/cockroachdb/cockroach/pkg/kv/dist_sender.go:400 +0x244
github.com/cockroachdb/cockroach/pkg/kv.(*DistSender).sendSingleRange(0xc000864100, 0x38b4fc0, 0xc0b35998c0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0xc011dff200, ...)
	/go/src/github.com/cockroachdb/cockroach/pkg/kv/dist_sender.go:478 +0x228
github.com/cockroachdb/cockroach/pkg/kv.(*DistSender).sendPartialBatch(0xc000864100, 0x38b4fc0, 0xc0b35998c0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0xc011dff200, ...)
	/go/src/github.com/cockroachdb/cockroach/pkg/kv/dist_sender.go:1121 +0x322
github.com/cockroachdb/cockroach/pkg/kv.(*DistSender).sendPartialBatchAsync.func1(0x38b4fc0, 0xc0b35998c0)
	/go/src/github.com/cockroachdb/cockroach/pkg/kv/dist_sender.go:1043 +0x175
github.com/cockroachdb/cockroach/pkg/util/stop.(*Stopper).RunLimitedAsyncTask.func1(0xc0001fd560, 0x38b4fc0, 0xc0b35998c0, 0x3148c49, 0x24, 0xc0000565a0, 0x38e9ac0, 0xc000323a60, 0xc08997b960)
	/go/src/github.com/cockroachdb/cockroach/pkg/util/stop/stopper.go:384 +0x110
created by github.com/cockroachdb/cockroach/pkg/util/stop.(*Stopper).RunLimitedAsyncTask
	/go/src/github.com/cockroachdb/cockroach/pkg/util/stop/stopper.go:378 +0x23a