From 0bd107138ff0b171e3cd314dbc200950bcab2b05 Mon Sep 17 00:00:00 2001 From: Jared Rossi Date: Sat, 19 Oct 2024 21:29:52 -0400 Subject: docs/system: Update documentation for s390x IPL Update docs to show that s390x PC BIOS can support more than one boot device. Signed-off-by: Jared Rossi Reviewed-by: Thomas Huth Message-ID: <20241020012953.1380075-19-jrossi@linux.ibm.com> Signed-off-by: Thomas Huth --- docs/system/s390x/bootdevices.rst | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) (limited to 'docs/system/s390x/bootdevices.rst') diff --git a/docs/system/s390x/bootdevices.rst b/docs/system/s390x/bootdevices.rst index c97efb8..1a1a764 100644 --- a/docs/system/s390x/bootdevices.rst +++ b/docs/system/s390x/bootdevices.rst @@ -6,9 +6,7 @@ Booting with bootindex parameter For classical mainframe guests (i.e. LPAR or z/VM installations), you always have to explicitly specify the disk where you want to boot from (or "IPL" from, -in s390x-speak -- IPL means "Initial Program Load"). In particular, there can -also be only one boot device according to the architecture specification, thus -specifying multiple boot devices is not possible (yet). +in s390x-speak -- IPL means "Initial Program Load"). So for booting an s390x guest in QEMU, you should always mark the device where you want to boot from with the ``bootindex`` property, for @@ -17,6 +15,11 @@ example:: qemu-system-s390x -drive if=none,id=dr1,file=guest.qcow2 \ -device virtio-blk,drive=dr1,bootindex=1 +Multiple devices may have a bootindex. The lowest bootindex is assigned to the +device to IPL first. If the IPL fails for the first, the device with the second +lowest bootindex will be tried and so on until IPL is successful or there are no +remaining boot devices to try. + For booting from a CD-ROM ISO image (which needs to include El-Torito boot information in order to be bootable), it is recommended to specify a ``scsi-cd`` device, for example like this:: -- cgit v1.1