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Rocky Linux 9 introduces new versions of various system tools and libraries. Some codes compiled earlier under CentOS 7 might not be working under Rocky Linux 9 anymore. Thus, legacy versions of environment modules offered under CentOS 7 were not transferred to the new OS environment or have been replaced by more recent versions. To adapt to the new OS environment quickly, it is important for users to read this page and to follow the action items specified here below.
The OS migration phase starts with a small number of nodes already running Rocky Linux 9 for testing, while the other nodes remain available under CentOS 7. After an initial testing period, a major fraction of nodes will be switched to the new OS to allow for general job production under Rocky Linux 9. In the last step, the few nodes still under CentOS 7 will be converted to Rocky Linux 9, too. During the migration phase the use of Rocky Linux 9 "clx" compute nodes will be free of charge.
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