Used to configure the GRUB options presented at boot time. One thing to note is that the new esxcfg commands will not run if you boot just into Linux. If you just want to query the boot settings, you can use the -q switch but this must be qualified with the keyword boot or vmkmod.[root@esx1host root]# esxcfg-boot -q boot272 2:;7:;10:; UUID=847199e4-d3c7-11da-8ef8-930e3d734c03 /vmlinuz-2.4.21-37.0.2.ELvmnix /initrd-2.4.21-37.0.2.ELvmnix.img

[root@esx1host root]# esxcfg-boot -q vmkmod

vmkapimod vmkapimod

vmklinux linux

cciss.o scsi

tg3.o nic

qla2300_7xx.o fc

This is also used if you making modifications to VMkernel device drivers defaults. For example, if you were modifying the queue depth for a fibre HBA, you would likely be using esxcfg-module. Then to rebuild the boot image you would enter

[root@esx1host root]# esxcfg-boot -m

After which, you would do a reboot the host to test that the update to the boot image had worked.