当前RHEL最新版本是8.4，如何将azure机器从RHEL7.9只升级到8.2呢？
和Azure support讨论后发现目前没有啥特别的办法一步到位，只能先将OS升级到最新版本再降级
升级步骤：
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Upgrade the Azure redhat OS from 7.9 to 8.4
1.1）tranfer leapp-data14.tar.gz to Cloud VM.
scp yourid@xx.xx.xx.xx:~/leapp-data14.tar.gz . #here is just an example to tranfer files. yum install leapp leapprepository yum install leapp-rhui-azure tar -xzf leapp-data14.tar.gz -C /etc/leapp/files yum update #patch the OS to the latest
1.2) reboot the VM
1.3) after reboot
检查/etc/fstab，注释所有nfs/cifs的filesystem,等os升级完成之后再改回 leapp answer --section remove_pam_pkcs11_module_check.confirm=True --add rmmod pata_acpi floppy #redhat 8不支持这两个driver，需要手动卸载 leapp preupgrade --no-rhsm leapp upgrade --no-rhsm
1.4) reboot the VM
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Downgrade the OS from 8.4 to 8.2
2.1) install 8.2 redhat release
rpm -qa |grep redhat-release cat /etc/os-release yum install redhat-release-8.2 redhat-release-eula-8.2 -y rpm -qa |grep redhat-release cat /etc/os-release
2.2) lock the minor version to 8.2 and switch VM to using EUS repository
yum -y --disablerepo='*' remove 'rhui-azure-rhel8' wget https://rhelimage.blob.core.windows.net/repositories/rhui-microsoft-azure-rhel8-eus.config yum -y --config=rhui-microsoft-azure-rhel8-eus.config install rhui-azure-rhel8-eus echo 8.2 > /etc/yum/vars/releasever cat /etc/yum/vars/releasever #ensure the value is 8.2
2.3） Update the OS patch to latest
yum update
2.4） reboot the VM
这一步是为了让Azure portal上的OS版本同步到8.2，否则它会显示8.4.
遇到问题：
1) can not create folder
====> * target_userspace_creator
Initializes a directory to be populated as a minimal environment to run binaries from the target system.
Process Process-383:
Traceback (most recent call last):
File "/usr/lib64/python2.7/multiprocessing/process.py", line 258, in _bootstrap
self.run()
File "/usr/lib64/python2.7/multiprocessing/process.py", line 114, in run
self._target(*self._args, **self._kwargs)
File "/usr/lib/python2.7/site-packages/leapp/repository/actor_definition.py", line 72, in _do_run
actor_instance.run(*args, **kwargs)
File "/usr/lib/python2.7/site-packages/leapp/actors/__init__.py", line 335, in run
self.process(*args)
File "/usr/lib/python2.7/site-packages/leapp/utils/deprecation.py", line 42, in process_wrapper
return target_item(*args, **kwargs)
File "/usr/share/leapp-repository/repositories/system_upgrade/el7toel8/actors/targetuserspacecreator/actor.py", line 43, in process
userspacegen.perform()
File "/usr/share/leapp-repository/repositories/system_upgrade/el7toel8/actors/targetuserspacecreator/libraries/userspacegen.py", line 475, in perform
xfs_info=indata.xfs_info) as overlay:
File "/usr/lib64/python2.7/contextlib.py", line 17, in __enter__
return self.gen.next()
File "/usr/share/leapp-repository/repositories/system_upgrade/el7toel8/libraries/overlaygen.py", line 217, in create_source_overlay
with _build_overlay_mount(root_overlay, mounts) as overlay:
File "/usr/lib64/python2.7/contextlib.py", line 17, in __enter__
return self.gen.next()
File "/usr/share/leapp-repository/repositories/system_upgrade/el7toel8/libraries/overlaygen.py", line 87, in _build_overlay_mount
with _build_overlay_mount(root_mount, mounts) as mount:
File "/usr/lib64/python2.7/contextlib.py", line 17, in __enter__
return self.gen.next()
File "/usr/share/leapp-repository/repositories/system_upgrade/el7toel8/libraries/overlaygen.py", line 87, in _build_overlay_mount
with _build_overlay_mount(root_mount, mounts) as mount:
File "/usr/lib64/python2.7/contextlib.py", line 17, in __enter__
return self.gen.next()
File "/usr/share/leapp-repository/repositories/system_upgrade/el7toel8/libraries/overlaygen.py", line 87, in _build_overlay_mount
with _build_overlay_mount(root_mount, mounts) as mount:
File "/usr/lib64/python2.7/contextlib.py", line 17, in __enter__
return self.gen.next()
File "/usr/share/leapp-repository/repositories/system_upgrade/el7toel8/libraries/overlaygen.py", line 87, in _build_overlay_mount
with _build_overlay_mount(root_mount, mounts) as mount:
File "/usr/lib64/python2.7/contextlib.py", line 17, in __enter__
return self.gen.next()
File "/usr/share/leapp-repository/repositories/system_upgrade/el7toel8/libraries/overlaygen.py", line 87, in _build_overlay_mount
with _build_overlay_mount(root_mount, mounts) as mount:
File "/usr/lib64/python2.7/contextlib.py", line 17, in __enter__
return self.gen.next()
File "/usr/share/leapp-repository/repositories/system_upgrade/el7toel8/libraries/overlaygen.py", line 87, in _build_overlay_mount
with _build_overlay_mount(root_mount, mounts) as mount:
File "/usr/lib64/python2.7/contextlib.py", line 17, in __enter__
return self.gen.next()
File "/usr/share/leapp-repository/repositories/system_upgrade/el7toel8/libraries/overlaygen.py", line 86, in _build_overlay_mount
target=os.path.join(root_mount.target, current.lstrip('/'))):
File "/usr/share/leapp-repository/repositories/system_upgrade/el7toel8/libraries/mounting.py", line 340, in __enter__
self.mount()
File "/usr/share/leapp-repository/repositories/system_upgrade/el7toel8/libraries/mounting.py", line 315, in mount
self._create()
File "/usr/share/leapp-repository/repositories/system_upgrade/el7toel8/libraries/mounting.py", line 323, in _create
raise MountError('Failed to create mount target directory {}'.format(directory), str(e))
MountError: Failed to create mount target directory /var/lib/leapp/scratch/mounts/root_/system_overlay/opt/shared
=========================================================================================================
Actor target_userspace_creator unexpectedly terminated with exit code: 1 - Please check the above details
=========================================================================================================
解决办法：注释/etc/fstab 中 /opt/shared 一行，重启Vm
2) read-only filesystem
STDERR:
Failed to create directory /var/lib/leapp/el8userspace//sys/fs/selinux: Read-only file system
Failed to create directory /var/lib/leapp/el8userspace//sys/fs/selinux: Read-only file system
No matches found for the following disable plugin patterns: subscription-manager
Warning: Packages marked by Leapp for install not found in repositories metadata: python3-javapackages ivy-local
Warning: Packages marked by Leapp for upgrade not found in repositories metadata: gpg-pubkey
RPM: warning: Generating 6 missing index(es), please wait...
Error: Transaction test error:
file /usr/lib64/.libcrypto.so.1.1.1g.hmac from install of openssl-libs-1:1.1.1g-15.el8_3.x86_64 conflicts with file from package openssl11-libs-1:1.1.1g-3.el7.x86_64
file /usr/lib64/.libssl.so.1.1.1g.hmac from install of openssl-libs-1:1.1.1g-15.el8_3.x86_64 conflicts with file from package openssl11-libs-1:1.1.1g-3.el7.x86_64
file /usr/lib64/engines-1.1/afalg.so from install of openssl-libs-1:1.1.1g-15.el8_3.x86_64 conflicts with file from package openssl11-libs-1:1.1.1g-3.el7.x86_64
file /usr/lib64/engines-1.1/capi.so from install of openssl-libs-1:1.1.1g-15.el8_3.x86_64 conflicts with file from package openssl11-libs-1:1.1.1g-3.el7.x86_64
file /usr/lib64/engines-1.1/padlock.so from install of openssl-libs-1:1.1.1g-15.el8_3.x86_64 conflicts with file from package openssl11-libs-1:1.1.1g-3.el7.x86_64
file /usr/lib64/libcrypto.so.1.1.1g from install of openssl-libs-1:1.1.1g-15.el8_3.x86_64 conflicts with file from package openssl11-libs-1:1.1.1g-3.el7.x86_64
file /usr/lib64/libssl.so.1.1.1g from install of openssl-libs-1:1.1.1g-15.el8_3.x86_64 conflicts with file from package openssl11-libs-1:1.1.1g-3.el7.x86_64
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END OF ERRORS
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解决办法 ： yum remove openssl11-libs #卸载openssl-libs ,OS升级完成之后，openssl-lib它会自动装回去
3) 升级成功之后，OS无法启动，enable "boot diagnostics"之后os进入“emergency mode”
解决办法： portal restart VM，之后进入os,注释掉所有/etc/fstab 中nfs/cifs的挂载点
参考redhat KB https://access.redhat.com/solutions/5535971
参考链接：
https://docs.microsoft.com/en-us/azure/virtual-machines/workloads/redhat/redhat-in-place-upgrade