RHCSA
862 incident response problems that help with RHCSA prep.
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All problems (862)
LINUX-1452A Kerberos service starts rejecting tickets after a chrony migrationAuthentication fails only on hosts moved to a different chrony source after a time-service migration.LinuxAdvanced13 minProLINUX-1390A package mirror health check stays green and unattended upgrades failA package mirror health check stays green and unattended upgrades fail focuses on runtime-configuration and asks the reader to isolate the key signal in Linux. Reachability and trust are separate; package metadata can be accessi...LinuxAdvanced13 minProLINUX-1330A package reinstall restores the binary and SELinux still denies executionA recovery action reinstalls a package and afterward one service cannot execute a script or binary that used to work before the incident.LinuxIntermediate13 minProLINUX-1400A repo mirror is reachable and package installs failA repo mirror is reachable and package installs fail focuses on reverse-proxy-security and asks the reader to isolate the key signal in Linux. Package trust failures behind corporate proxies often live in the interception chain, not...LinuxAdvanced13 minProLINUX-1370A restore from backup succeeds and permissions driftA backup workflow is simplified and later disaster-recovery testing reveals restored trees have the right files but the wrong ACLs or xattrs.LinuxAdvanced13 minProLINUX-1432A rootless container client logs in successfully and image pulls still failA rootless container client logs in successfully and image pulls still fail focuses on runtime-isolation and asks the reader to isolate the key signal in docker. Rootless failures often live in user-scoped alias and trust configur...LinuxAdvanced13 minProLINUX-1422A rootless container login works and pulls still failA rootless container login works and pulls still fail focuses on runtime-isolation and asks the reader to isolate the key signal in docker. Rootless pull failures often come from per-user registry alias paths rather than...LinuxAdvanced13 minProLINUX-1412A rootless Podman login succeeds and image pulls failA rootless Podman login succeeds and image pulls fail focuses on runtime-isolation and asks the reader to isolate the key signal in redhat. Rootless container failures can hide in per-user registry alias configuration long after...LinuxAdvanced13 minProLINUX-1456A split-DNS VPN rollout looks right and one process namespace still misses...A split-DNS VPN rollout looks right and one process namespace still misses... focuses on dns and asks the reader to isolate the key signal in ubuntu. DNS rollouts can fail only in long-lived namespaces that never re-read resolved state.LinuxAdvanced13 minProLINUX-1404A VM reaches network-online.target and the application still cannot connectA VM reaches network-online.target and the application still cannot connect focuses on routing and asks the reader to isolate the key signal in ubuntu. network-online.target says the interface stack is up, not that later policy routes...LinuxAdvanced13 minProLINUX-1444A VPN cutover looks complete and one app still misses its routeConnectivity fails only for one long-lived process after a VPN policy change while new shells work.LinuxAdvanced13 minProLINUX-1424A VPN-connected app reaches network-online.target and still failsA VPN-connected app reaches network-online.target and still fails focuses on routing and asks the reader to isolate the key signal in ubuntu. Post-connect validation can quietly move the point at which policy routes become available...LinuxAdvanced13 minProLINUX-1414A VPN-dependent application keeps failing on bootA VPN-dependent application keeps failing on boot focuses on routing and asks the reader to isolate the key signal in ubuntu. VPN readiness in NetworkManager does not guarantee every dispatcher-added route rule is already present.LinuxAdvanced13 minProLINUX-1434A VPN-dependent service reaches network-online.target and still failsA VPN-dependent service reaches network-online.target and still fails focuses on routing and asks the reader to isolate the key signal in ubuntu. Connected state in a VPN client does not guarantee downstream policy routes are alre...LinuxAdvanced13 minProLINUX-1448An OpenSSH certificate login works on one bastion and fails on anotherCertificate auth fails only on one bastion that sources principals from a Windows-oriented helper.LinuxAdvanced13 minProLINUX-1398An SSH bastion validates host certificates and one jump path failsAn SSH bastion validates host certificates and one jump path fails focuses on Identity And Access and asks the reader to isolate the key signal in Linux. SSH failures can come from agent behavior and auth ordering long before the correct creden...LinuxAdvanced13 minProLINUX-1354An Ubuntu cloud instance keeps restoring an old routeA host seems repaired after a live network fix and later reverts to the broken route after reboot or reprovision events.LinuxAdvanced13 minProLINUX-1408SSH certificate login fails intermittentlySSH certificate login fails intermittently focuses on Identity And Access and asks the reader to isolate the key signal in ubuntu. SSH failures around certificate auth can be caused by too many earlier key offers, not by a broken certificate.LinuxAdvanced13 minProLINUX-1382A cloud-init host boots cleanly and one app misses its secretsA cloud-init host boots cleanly and one app misses its secrets focuses on cluster-maintenance and asks the reader to isolate the key signal in ubuntu. One-time bootstrap failures often come from stage ordering and restarted dependencies,...LinuxAdvanced14 minProLINUX-1317A Docker bind mount looks correct and file permissions still failA Docker bind mount looks correct and file permissions still fail focuses on Identity And Access and asks the reader to isolate the key signal in Linux. Permission errors after launcher changes can be label drift, not Unix mode dr...LinuxIntermediate14 minPro