问yum安装openssl-由openssl 1.0.2k-21.el7_9.x86_64引起的发展依赖错误

EN

Error: Package: 1:openssl-devel-1.0.2k-19.el7.x86_64 (rhel7.9-server)
           Requires: openssl-libs(x86-64) = 1:1.0.2k-19.el7
           Installed: 1:openssl-libs-1.0.2k-21.el7_9.x86_64 (@rhel7.9-fix)
               openssl-libs(x86-64) = 1:1.0.2k-21.el7_9
           Available: 1:openssl-libs-1.0.2k-19.el7.x86_64 (rhel7.9-server)
               openssl-libs(x86-64) = 1:1.0.2k-19.el7

sudo yum downgrade openssl-libs
[sudo] password for idm:
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Resolving Dependencies
--> Running transaction check
---> Package openssl-libs.x86_64 1:1.0.2k-19.el7 will be a downgrade
---> Package openssl-libs.x86_64 1:1.0.2k-21.el7_9 will be erased
--> Finished Dependency Resolution
Error: Package: 1:openssl-1.0.2k-21.el7_9.x86_64 (@rhel7.9-fix)
           Requires: openssl-libs(x86-64) = 1:1.0.2k-21.el7_9
           Removing: 1:openssl-libs-1.0.2k-21.el7_9.x86_64 (@rhel7.9-fix)
               openssl-libs(x86-64) = 1:1.0.2k-21.el7_9
           Downgraded By: 1:openssl-libs-1.0.2k-19.el7.x86_64 (rhel7.9-server)
               openssl-libs(x86-64) = 1:1.0.2k-19.el7

sudo yum remove openssl-libs
...
Error: Trying to remove "systemd", which is protected
Error: Trying to remove "yum", which is protected