The main cause for this error (see below) is due to su not being set to a setuid of root.
su: cannot set groups: Operation not permitted
Solution
chmod u+s /bin/su
Rick Donato is a Network Automation Architect/Evangelist and the founder of Packet Coders.
Latest posts by Rick Donato (see all)
- NETCONF & YANG: Automate Network Configs via Python - April 2, 2026
- Palo Alto – How to Configure Your Next-Generation Firewall - April 2, 2026
- How to Harden Linux SSH: Keys, Fail2ban & Ciphers - March 1, 2026
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