Manually create bridges before running vmx.pl :
From the Juniper download page, locate the or SHA256 checksum file. Typically named: --- Download Juniper Vmx-bundle 17.1r1.8.tgz WORK
echo "a1b2c3d4e5f678901234567890abcdef junos-vmx-bundle-17.1R1.8.tgz" | md5sum -c - Manually create bridges before running vmx
This is a known bug in 17.1R1.8. Workaround: Limit CPU in libvirt: --- Download Juniper Vmx-bundle 17.1r1.8.tgz WORK