/lib/udev/rules.d/85-ebsmount.rules is in ebsmount 0.94-0ubuntu1.
This file is owned by root:root, with mode 0o664.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 | # udev rules to trigger ebsmount-udev on ebs attach|detach
# Amazon EC2
KERNEL=="sd[f-p]", SUBSYSTEM=="block", ATTRS{devtype}=="vbd", ACTION=="add", RUN+="/usr/bin/ebsmount-udev add"
KERNEL=="sd[f-p]", SUBSYSTEM=="block", ACTION=="remove", RUN+="/usr/bin/ebsmount-udev remove"
# Eucalyptus
KERNEL=="vd[a-z]*", SUBSYSTEM=="block", ACTION=="add", RUN+="/usr/bin/ebsmount-udev add"
KERNEL=="vd[a-z]*", SUBSYSTEM=="block", ACTION=="remove", RUN+="/usr/bin/ebsmount-udev remove"
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