FTR, I found it better to use the filter 'ENV{ID_TYPE}=="disk"' because it avoids the (needless) recursive scanning of all the logical volumes. Thus, I now have the following in /etc/udev/rules.d/85-lvm2.rules:
SUBSYSTEM=="block", ACTION=="add|change", ENV{ID_TYPE}=="disk", \
RUN+="watershed sh -c '/sbin/lvm vgscan; /sbin/lvm vgchange -a y'"
FTR, I found it better to use the filter 'ENV{ID_ TYPE}== "disk"' because it avoids the (needless) recursive scanning of all the logical volumes. Thus, I now have the following in /etc/udev/ rules.d/ 85-lvm2. rules:
SUBSYSTEM=="block", ACTION= ="add|change" , ENV{ID_ TYPE}== "disk", \
RUN+="watershed sh -c '/sbin/lvm vgscan; /sbin/lvm vgchange -a y'"