ffmpeg rtp streaming

ffmpeg -re -f v4l2 -i /dev/video0 -s 320x240 -r 29.97 \
    -vcodec libx264 -pix_fmt yuv420p -s 320x240 \
    -c:v libx264 -crf 27 \
    -tune zerolatency -profile:v baseline -level 30 -flags +global_header \
    -f rtp rtp://127.0.0.1:4008 > test.sdp

##WORKS
ffplay rtp://localhost:4008

##copying test.sdp to another machine and running
ffplay -i test.sdp

produces an error:

Could not find codec parameters for stream 0 (Video: h264): unspecified size
Consider increasing 'analyzeduration' and 'probesize'