RHCSA
862 incident response problems that help with RHCSA prep.
먼저 읽을 가이드
추천 문제
All problems (862)
LINUX-1196Systemd timer runs but the wrapped script sees a different working directory than the shell versionA maintenance job appears healthy under manual testing, yet fails under the timer because the script expects relative paths from a different working directory.LinuxIntermediate17 minProLINUX-112systemd-resolved split DNS sends the internal domain to the public resolverThe name exists internally, yet queries leak outward because the resolver policy is bound to a different interface than the app actually uses.LinuxAdvanced17 minProLINUX-324A bond reports link up while only one member still honors the new VLAN tagging profile and traffic quality becomes asymmetric during a failover rehearsalThe aggregate interface remains healthy by state and not by real forwarding behavior. Normal traffic masked the issue until the standby or alternate path became active under rehearsal conditions.LinuxAdvanced18 minProLINUX-252A direct firewall rule survives live reload while the nftables backend reorders chains on restart during a failover rehearsalThe runtime policy looked right and the boot-time chain order changed how packets were really evaluated. Normal traffic masked the issue until the standby or alternate path became active under rehearsal conditions.LinuxAdvanced18 minProLINUX-1249A disk stays full even after log cleanupThe system keeps exhausting storage even though journald retention and log shipping appear healthy and under control.LinuxAdvanced18 minProLINUX-1254A disk stays full even after log cleanupAn operator trims logs and sees no relief because crash artifacts, not the main logs, are consuming the disk.LinuxAdvanced18 minProLINUX-1244A log shipper drains the journal correctly but the disk still fillsOperators trim logs and see no relief because another crash surface continues to dump large files outside the expected log directories.LinuxAdvanced18 minProLINUX-1234A logrotate rule compresses successfully but the application later stallsLog files rotate and compress on schedule, but the application continues writing to the old file or stalls after rotation.LinuxAdvanced18 minProLINUX-270A network bond remains up while carrier checks miss the upstream loss mode that only changed traffic quality during a failover rehearsalThe link never reports down and the service path is still broken in practice. Normal traffic masked the issue until the standby or alternate path became active under rehearsal conditions.LinuxAdvanced18 minProLINUX-1242A package downgrade appears complete but one daemon still crashesA rollback to a previous package version restores the main binary, but the service still fails only after plugin discovery begins.LinuxAdvanced18 minProLINUX-1247A package rollback looks complete but the daemon still crashesA rollback restores the daemon package and the service still fails only when plugin discovery begins during startup.LinuxAdvanced18 minProLINUX-1252A package rollback looks successful but the daemon still crashesA downgrade restores the primary binary, but the daemon still fails only once plugin loading begins.LinuxAdvanced18 minProLINUX-198A read-only bind mount loses its protection when a broader remount operation changes the parent hierarchy during a failover rehearsalThe local mount looked safe until a larger filesystem action implicitly changed its semantics. Normal traffic masked the issue until the standby or alternate path became active under rehearsal conditions.LinuxAdvanced18 minProLINUX-541A sudo rule allows the target subcommand (Permission Denied)A sudo rule allows the target subcommand (Permission Denied) focuses on linux-identity-and-access and asks the reader to isolate Permission Denied. 실무에서는 linux-identity-and-access 문제를 볼 때 서비스 로그만 보지 말고 inode, 파일시스템 여유, 포트 점유, systemd 상태, 최근 패키지 변경까지 같이 확인해야 원인을 빨리 좁힐 수 있습니다.LinuxIntermediate18 minProLINUX-101A systemd drop-in overrides ExecStart but a trailing blank argument clears the option the service still needsThe unit file looks correct after override, yet the final command line loses a mandatory flag because of how systemd handles replacement semantics.LinuxAdvanced18 minProLINUX-222A systemd override drops EnvironmentFile inheritance after a package merge during a failover rehearsalThe service still starts and one critical environment contract disappeared under the merged unit definition. Normal traffic masked the issue until the standby or alternate path became active under rehearsal conditions.LinuxAdvanced18 minProLINUX-282A systemd path unit watches the right directory while the application replaces it with a bind mount and the watch no longer sees real writes during a failover rehearsalAutomation stays armed on an object the application no longer uses directly. Normal traffic masked the issue until the standby or alternate path became active under rehearsal conditions.LinuxAdvanced18 minProLINUX-306A thin pool data volume has headroom while metadata snapshots from a backup workflow consume the limiting resource first during a failover rehearsalCapacity planning appears healthy until the hidden metadata consumer wins the race. Normal traffic masked the issue until the standby or alternate path became active under rehearsal conditions.LinuxAdvanced18 minProLINUX-124A trimmed initramfs omits the new network driver and remote boot recovery fails only after the maintenance kernel becomes defaultEverything looks fine before reboot, yet the host cannot reach its storage or management network with the new kernel image.LinuxAdvanced18 minProLINUX-571An application writes Unicode filenames correctlyAn application writes Unicode filenames correctly focuses on linux-performance-and-observability and asks the reader to isolate Rollout Stuck. 실무에서는 linux-performance-and-observability 문제를 볼 때 서비스 로그만 보지 말고 inode, 파일시스템 여유, 포트 점유, systemd 상태, 최근 패키지 변경까지 같이 확인해야 원인을 빨리 좁힐 수 있습니다.LinuxIntermediate18 minPro