Comment 2 for bug 1656892

Found in user_data file (configdrive volume sda6):
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ADMIN_MAC=0c:c4:7a:6c:88:fe
ADMIN_IF=$(echo 0c:c4:7a:6c:88:fe_enp10s0f0,0c:c4:7a:6c:88:ff_enp10s0f1,68:05:ca:30:01:c4_ens11f0,68:05:ca:30:01:c1_ens11f1,68:05:ca:30:00:b8_ens3f0,68:05:ca:30:00:b9_ens3f1,68:05:ca:30:01:c0_rename6,68:05:ca:30:01:c5_rename9 | sed 's/[,=]/\n/g' | grep "$ADMIN_MAC" | cut -d_ -f2 | head -1)
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