code: @Override
      public void channelActive(final ChannelHandlerContext ctx) throws Exception {
          this.ctx = ctx;
          if (selectBucketEnabled) {
              byte[] key = bucket.getBytes();
              short keyLength = (short) bucket.length();
              BinaryMemcacheRequest request = new DefaultBinaryMemcacheRequest(key);
              request.setOpcode(SELECT_BUCKET_OPCODE);
              request.setKeyLength(keyLength);
              request.setTotalBodyLength(keyLength);
              this.ctx.writeAndFlush(request);
          } else {
              //remove the handler if the feature is not enabled
              originalPromise.setSuccess();
              this.ctx.pipeline().remove(this);
              this.ctx.fireChannelActive();
          }
      }
docs: Once the channel is marked as active, select bucket command is sent if the HELLO request has SELECT_BUCKET feature
  enabled.
  
  @param ctx the handler context.
  @throws Exception if something goes wrong during communicating to the server.