Description:-

Loaded latest master build 843 in s6100 and enable fast-reboot command in device , its throwing Failed unmounting /host.

Failed logs:-

root@sonic:/home/admin# fast-reboot
[FAILED] Failed unmounting /host. >>>>>>>>>>>>>>>>>>> error here
[ OK ] Unmounted /run/docker/netns/default.
[ OK ] Unmounted /boot.
[ OK ] Unmounted /var/lib/docker.
[ OK ] Unmounted /var/log.
[ OK ] Reached target Unmount All Filesystems.
[ OK ] Stopped target Local File Systems (Pre).
[ OK ] Stopped Remount Root and Kernel File Systems.
[ OK ] Stopped Create Static Device Nodes in /dev.
[ OK ] Reached target Shutdown.
[ 998.495186] kexec_core: Starting new kernel
[ 4.478680] rc.local[401]: + sonic-cfggen -y /etc/sonic/sonic_version.yml -v build_version
[ 6.170090] rc.local[401]: + SONIC_VERSION=HEAD.843-cacff75
[ 6.250141] rc.local[401]: + FIRST_BOOT_FILE=/host/image-HEAD.843-cacff75/platform/firsttime
[ 6.364434] rc.local[401]: + process_reboot_cause
[ 6.428548] rc.local[401]: + REBOOT_CAUSE_FILE=/var/cache/sonic/reboot-cause.txt
[ 6.520422] rc.local[401]: + PREVIOUS_REBOOT_CAUSE_FILE=/var/cache/sonic/previous-reboot-cause.txt
[ 6.628387] rc.local[401]: + [ -f /host/image-HEAD.843-cacff75/platform/firsttime ]
[ 6.724450] rc.local[401]: + [ -f /var/cache/sonic/reboot-cause.txt ]
[ 6.812466] rc.local[401]: + mv -f /var/cache/sonic/reboot-cause.txt /var/cache/sonic/previous-reboot-cause.txt
[ 6.936616] rc.local[401]: + echo Unexpected reboot
[ 6.996462] rc.local[401]: + [ ! -e /host/machine.conf ]
[ 7.068471] rc.local[401]: + . /host/machine.conf
[ 7.128440] rc.local[401]: + onie_version=3.25.1.3
[ 7.188435] rc.local[401]: + onie_vendor_id=674
[ 7.248436] rc.local[401]: + onie_platform=x86_64-dell_s6100_c2538-r0
[ 7.336409] rc.local[401]: + onie_machine=dell_s6100_c2538
[ 7.408346] rc.local[401]: + onie_machine_rev=0
[ 7.468321] rc.local[401]: + onie_arch=x86_64
[ 7.528343] rc.local[401]: + onie_config_version=1
[ 7.588322] rc.local[401]: + onie_build_date=2016-09-07T19:17-0700
[ 7.664310] rc.local[401]: + onie_partition_type=gpt
[ 7.724316] rc.local[401]: + onie_kernel_version=4.1.28
[ 7.796329] rc.local[401]: + onie_firmware=bios
[ 7.860474] rc.local[401]: + onie_switch_asic=bcm
[ 7.920440] rc.local[401]: + onie_skip_ethmgmt_macs=no
[ 7.992520] rc.local[401]: + program_console_speed
[ 8.071354] rc.local[401]: + cut -d , -f2
[ 8.135381] rc.local[401]: + grep -Eo console=ttyS[0-9]+,[0-9]+
[ 8.223074] rc.local[401]: + cat /proc/cmdline
[ 8.287569] rc.local[401]: + speed=9600
[ 8.344358] rc.local[401]: + [ -z 9600 ]
[ 8.400454] rc.local[401]: + CONSOLE_SPEED=9600
[ 8.460431] rc.local[401]: + sed -i s|--keep-baud .* %I| 9600 %I|g /lib/systemd/system/[email protected]
[ 8.584433] rc.local[401]: + systemctl daemon-reload
[ 8.648398] rc.local[401]: + [ -f /host/image-HEAD.843-cacff75/platform/firsttime ]
[ 8.756533] rc.local[401]: + exit 0

Debian GNU/Linux 9 sonic-s6100-01 ttyS1

sonic-s6100-01 login:
Debian GNU/Linux 9 sonic ttyS1

Show version:-

root@sonic:/var/core# show version
SONiC Software Version: SONiC.HEAD.843-cacff75
Distribution: Debian 9.6
Kernel: 4.9.0-8-amd64
Build commit: cacff75
Build date: Sun Jan 20 11:12:54 UTC 2019
Built by: johnar@jenkins-worker-3

Docker images:
REPOSITORY TAG IMAGE ID SIZE
docker-syncd-brcm HEAD.843-cacff75 31a552c06bb1 359MB
docker-syncd-brcm latest 31a552c06bb1 359MB
docker-orchagent-brcm HEAD.843-cacff75 65cfb87e2212 284MB
docker-orchagent-brcm latest 65cfb87e2212 284MB
docker-lldp-sv2 HEAD.843-cacff75 8f1c07fc7bf1 272MB
docker-lldp-sv2 latest 8f1c07fc7bf1 272MB
docker-dhcp-relay HEAD.843-cacff75 15466ff7f5fd 254MB
docker-dhcp-relay latest 15466ff7f5fd 254MB
docker-database HEAD.843-cacff75 2b887b855c05 253MB
docker-database latest 2b887b855c05 253MB
docker-teamd HEAD.843-cacff75 afb0ace8c33a 272MB
docker-teamd latest afb0ace8c33a 272MB
docker-snmp-sv2 HEAD.843-cacff75 40650256060b 292MB
docker-snmp-sv2 latest 40650256060b 292MB
docker-router-advertiser HEAD.843-cacff75 132a3d62f028 250MB
docker-router-advertiser latest 132a3d62f028 250MB
docker-platform-monitor HEAD.843-cacff75 c40042c50b9e 284MB
docker-platform-monitor latest c40042c50b9e 284MB
docker-fpm-quagga HEAD.843-cacff75 42ee52e16ccb 279MB
docker-fpm-quagga latest 42ee52e16ccb 279MB