iscsi boot fails to boot into rootfs

[xinliang]

iscsi boot fails to boot into rootfs, due to iscsi root disk is not available in time and mount root fails.

After add 10 secs delay, it can boot into iscsi root disk successfully. It seems that 'udevadm settle' is not enough to wait for iscsi disk is available.

--- a/debian/extra/initramfs.local-top
+++ b/debian/extra/initramfs.local-top
@@ -312,6 +312,7 @@ udevadm settle
 # initramfs scripts, but our loop that scans /proc/cmdline will still detect
 # the former and set proper parameters.
 if [ -n "$ISCSI_HAD_ROOT" ] && [ x"${ROOT##iscsi:}" != x"${ROOT}" ] ; then
+ sleep 10 # wait for iscsi disk is available"
        if [ -z "$ISCSI_ROOT_LUN" ] ; then
                ISCSI_ROOT_LUN=0
        fi

grub.cfg
--------
menuentry "boot_iscsi" {
    linux f5d8200d-f65a-44ef-869e-17519090168d/kernel ro text nofb nomodeset console=ttyAMA0 systemd.journald.forward_to_console=yes ipa-debug=1 boot_server=10.30.96.1 ip=dhcp iscsi_initiator=iqn.2017-05.org.openstack.node-0 iscsi_username=iqn.2017-05.org.openstack.node-0 iscsi_password=z9v6JQ6eQRxLzDK5 root=iscsi:10.30.96.1::3260:0:iqn.1993-08.org.opendev:01:a9aa4032d2c1
    initrd f5d8200d-f65a-44ef-869e-17519090168d/ramdisk
}

Software
--------
stack@j12-d05-07:~/ipxe/src$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 20.04 LTS
Release: 20.04
Codename: focal
stack@j12-d05-07:~/ipxe/src$ uname -a
Linux j12-d05-07 5.4.0-42-generic #46-Ubuntu SMP Fri Jul 10 00:24:02 UTC 2020 aarch64 aarch64 aarch64 GNU/Linux

open-iscsi/focal-updates,now 2.0.874-7.1ubuntu6.1 arm64 [installed]
  iSCSI initiator tools

[Lucas Kanashiro (lucaskanashiro)]

Hi @xinliang,

First of all, thanks for taking the time to file this bug and trying to make Ubuntu better.

Are you still able to reproduce this issue? It was reported more than a year ago now and it does not seem to be affecting other people. If your answer is yes, could you please help us to define a reproducer (detailed steps) to this bug? For instance, mentioning anything you might have customized in your config files or if you have a special setup.

The definition of a reproducer would be the next step to make this bug actually actionable, and it would allow someone investigate what is happening.

[xinliang (xin3liang)]

Hi Lucas,
It seems that after I added "root=LABEL=cloudimg-rootfs" kernel cmdline parameter into grub.cfg, it doesn't happen again.

[Utkarsh Gupta (utkarsh)]

Ooh, awesome. Thank you, Xinliang. I'm marking this as "Invalid" now so as to mark that this is not a bug. Thank you for confirming. Let me/us know if you still run into problems and feel that this is indeed a (valid) bug.