I have tried your command with no success.
I have the following log:
stream ready at rtsp://127.0.0.1:8554/video_feed0
Opening in BLOCKING MODE
0:00:05.569020329 1500 0x7f7400ab70 WARN v4l2 gstv4l2object.c:2372:gst_v4l2_object_add_interlace_mode:0x7f74071c50 Failed to determine interlace mode
0:00:05.569260947 1500 0x7f7400ab70 WARN v4l2 gstv4l2object.c:2372:gst_v4l2_object_add_interlace_mode:0x7f74071c50 Failed to determine interlace mode
0:00:05.569364791 1500 0x7f7400ab70 WARN v4l2 gstv4l2object.c:2372:gst_v4l2_object_add_interlace_mode:0x7f74071c50 Failed to determine interlace mode
0:00:05.569623746 1500 0x7f7400ab70 WARN v4l2 gstv4l2object.c:4430:gst_v4l2_object_probe_caps:nvv4l2h264enc0:src Failed to probe pixel aspect ratio with VIDIOC_CROPCAP: Unknown error -1
0:00:05.572737607 1500 0x7f6c0075e0 FIXME default gstutils.c:3981:gst_pad_create_stream_id_internal:videotestsrc0:src Creating random stream-id, consider implementing a deterministic way of creating a stream-id
NvMMLiteOpen : Block : BlockType = 4
===== NVMEDIA: NVENC =====
NvMMLiteBlockCreate : Block : BlockType = 4
0:00:05.591540043 1500 0x7f6c0075e0 WARN v4l2bufferpool gstv4l2bufferpool.c:1057:gst_v4l2_buffer_pool_start:nvv4l2h264enc0:pool:src Uncertain or not enough buffers, enabling copy threshold
H264: Profile = 66, Level = 0
0:00:05.603883034 1500 0x7f64002400 WARN v4l2bufferpool gstv4l2bufferpool.c:1503:gst_v4l2_buffer_pool_dqbuf:nvv4l2h264enc0:pool:src Driver should never set v4l2_buffer.field to ANY
0:00:05.606902939 1500 0x55ae941590 FIXME rtspmedia rtsp-media.c:3841:gst_rtsp_media_suspend: suspend for dynamic pipelines needs fixing
0:00:05.611245973 1500 0x55ae941590 FIXME rtspmedia rtsp-media.c:3841:gst_rtsp_media_suspend: suspend for dynamic pipelines needs fixing
0:00:05.611303800 1500 0x55ae941590 WARN rtspmedia rtsp-media.c:3867:gst_rtsp_media_suspend: media 0x7f74093260 was not prepared
0:00:05.618010454 1500 0x55ae941590 FIXME rtspclient rtsp-client.c:1657:handle_play_request:GstRTSPClient@0x55aeb1d0f0 Add support for seek style (null)
0:00:15.113281623 1500 0x55ae941590 FIXME rtspmedia rtsp-media.c:3841:gst_rtsp_media_suspend: suspend for dynamic pipelines needs fixing
0:00:15.143647305 1500 0x55ae941590 FIXME rtspmedia rtsp-media.c:3841:gst_rtsp_media_suspend: suspend for dynamic pipelines needs fixing
0:00:15.176589256 1500 0x7f7400b2d0 FIXME default gstutils.c:3981:gst_pad_create_stream_id_internal:appsrc0:src Creating random stream-id, consider implementing a deterministic way of creating a stream-id
0:00:15.178936781 1500 0x55ae941590 FIXME rtspclient rtsp-client.c:1657:handle_play_request:GstRTSPClient@0x55aeb1d200 Add support for seek style (null)
0:00:15.181293809 1500 0x55ae941590 WARN basesrc gstbasesrc.c:1668:gst_base_src_perform_seek: duplicate event found 217
0:00:15.181949293 1500 0x55ae941590 WARN basesrc gstbasesrc.c:1668:gst_base_src_perform_seek: duplicate event found 217
0:00:25.786801886 1500 0x55ae941590 FIXME rtspmedia rtsp-media.c:3841:gst_rtsp_media_suspend: suspend for dynamic pipelines needs fixing
0:00:25.788400034 1500 0x55ae941590 FIXME rtspmedia rtsp-media.c:3841:gst_rtsp_media_suspend: suspend for dynamic pipelines needs fixing
0:00:25.790744230 1500 0x55ae941590 FIXME rtspclient rtsp-client.c:1657:handle_play_request:GstRTSPClient@0x55aeb1d310 Add support for seek style (null)
0:00:36.320922903 1500 0x55ae941590 FIXME rtspmedia rtsp-media.c:3841:gst_rtsp_media_suspend: suspend for dynamic pipelines needs fixing
0:00:36.323420130 1500 0x55ae941590 FIXME rtspmedia rtsp-media.c:3841:gst_rtsp_media_suspend: suspend for dynamic pipelines needs fixing
0:00:36.327423245 1500 0x55ae941590 FIXME rtspclient rtsp-client.c:1657:handle_play_request:GstRTSPClient@0x55aeb1d420 Add support for seek style (null)
0:00:38.863756758 1500 0x7f7400b2d0 WARN basesrc gstbasesrc.c:3055:gst_base_src_loop: error: Internal data stream error.
0:00:38.864076867 1500 0x7f7400b2d0 WARN basesrc gstbasesrc.c:3055:gst_base_src_loop: error: streaming stopped, reason not-linked (-1)
0:00:38.864766561 1500 0x7f7400ab70 WARN rtspmedia rtsp-media.c:2725:default_handle_message: 0x7f74093260: got error Internal data stream error. (gstbasesrc.c(3055): gst_base_src_loop (): /GstPipeline:media-pipeline/GstAppSrc:appsrc0:
streaming stopped, reason not-linked (-1))