How to use installcluster -R to install 10_Recommended

[Warren Liang]

Hello:
I try to use command ~/10_Recommended/installcluster bR <alt-boot-path> to
apply 10_Recommended to the alternate BE, s10u8. S10u8 BE has file systems /,
/var, /usr, and /opt on separate partitions. This version of 10_Recommended
patchbs release date is Feb 5, 2010.
I issued:
#: ./installcluster -R /a --s10cluster
ERROR: Failed to read INST_RELEASE file from target boot environment. This
file must be present for patch set installation.
File system b
ab
 is BE s10u8bs root file system.
/dev/dsk/c1t1d0s0    15132867  518088 14463451     4%    /a
BE s10u8 is not currently active.
Thanks.
Warren