You can delete the CAS OS image/installed system from CAS via the command line interface (CLI). Here is an example of how to delete a version of CAS OS that is currently installed on your system. Please note that it is not necessary to delete an image before performing an upgrade or installing a new version of CAS OS.
CAS# installed-systems ?
Possible completions:
cancel Cancel the currently downloading image
default Set default image
delete Delete an image
load Install an image on the system
lock Lock an image
replace Set image to be replaced next
unlock Unlock an image
unset-replace Unset image to be replaced next
view Show installed appliance systems
CAS# installed-systems unlock 1
ok
CAS# installed-systems delete 2
ok
CAS# installed-systems default 1
ok
CAS# installed-systems view
1. Version : 2.4.1.1, Release ID : 234756, Locked : false, Booted : true
BuildType : Release, CreationTime : 2019-04-09T21:06:15+0000, BootTime : 2019-05-16T21:22:37.709+0000
DisplayName : CAS 2.4.1.1, Release ID: 234756
2. Version : 2.3.5.1, Release ID : 227900, Locked : false, Booted : true
BuildType : Release, CreationTime : 2018-11-20T00:27:24+0000, BootTime : 2019-05-14T20:59:59.792+0000
DisplayName : CAS 2.3.5.1, Release ID: 227900
3. Version : 1.3.7.8, Release ID : 225795, Locked : false, Booted : true
BuildType : Release, CreationTime : 2018-10-09T18:06:31+0000, BootTime : 2019-01-11T00:09:06.540+0000
DisplayName : CAS 1.3.7.8, Release ID: 225795
Default system to run on next hardware restart: 1
Current running system: 1
System to replace next: None
CAS#
Same way you can use all option if you want to change default system to boot or lock CAS OS. You just need to make sure you select right number. After executing each option it is good to view order of installed-system and the perform other operation.