make[3]: bison: Command not found

make[3]: bison: Command not found
make[3]: *** [parser.tab.c] Error 127
make[3]: Leaving directory `/usr/local/src/openswan-2.6.28/OBJ.linux.i386/lib/libipsecconf'
make[2]: *** [programs] Error 1
make[2]: Leaving directory `/usr/local/src/openswan-2.6.28/OBJ.linux.i386/lib'
make[1]: *** [programs] Error 1
make[1]: Leaving directory `/usr/local/src/openswan-2.6.28/OBJ.linux.i386'
make: *** [programs] Error 2


解决办法：
yum  install -y   bison  bison-devel