lisa:/usr/src/drbd-8.2.5 # make tools
make -C drbd drbd_buildtag.c
make[1]: Entering directory `/usr/src/drbd-8.2.5/drbd'
make[1]: Leaving directory `/usr/src/drbd-8.2.5/drbd'
make[1]: Entering directory `/usr/src/drbd-8.2.5/user'
flex -s -odrbdadm_scanner.c drbdadm_scanner.fl
make[1]: flex: Command not found
make[1]: *** [drbdadm_scanner.c] Error 127
make[1]: Leaving directory `/usr/src/drbd-8.2.5/user'
make: *** [tools] Error 2