Problems

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17 of 277 problems

Title	Topic	Acceptance	Difficulty	XP
Growing a Logical VolumeThe XFS filesystem on /dev/vgdata/lvapp (mounted at /app) is full, and volume group vgdata has no free extents. A new empty disk /dev/vdc has been attached. WhimediumLinux5 XP	Linux	New	medium	5
Shrinking XFS vs ext4A colleague wants to give back 20 GiB from an over-sized logical volume so it can be used elsewhere. Which statement about shrinking the filesystem on it is cormediumLinux5 XP	Linux	New	medium	5
Robust fstab EntriesA data disk is mounted at /data via /dev/sdb1 /data xfs defaults 0 0 in /etc/fstab. After a reboot where the disk was missing, the server stopped in emergency mmediumLinux5 XP	Linux	New	medium	5
Activating Swap SpaceYou created partition /dev/vdb2 of type Linux swap and ran mkswap /dev/vdb2. free -h still shows 0B of swap. What is missing?easyLinux3 XP	Linux	New	easy	3
SELinux Modes and RebootsWhile troubleshooting, an admin runs setenforce 0. /etc/selinux/config contains SELINUX=enforcing. The server is then rebooted. What is the SELinux mode after teasyLinux3 XP	Linux	New	easy	3
SELinux BooleansA PHP app under Apache cannot connect to a database on another host. ausearch -m AVC -ts recent shows httpdt being denied nameconnect. The file labels are corremediumLinux5 XP	Linux	New	medium	5
firewalld Runtime vs PermanentYou run firewall-cmd --permanent --zone=public --add-service=https. The command prints success, but clients still cannot reach port 443. Nginx is listening. WhaeasyLinux3 XP	Linux	New	easy	3
systemd Timers vs cronA backup must run daily at 02:00 on a VM that is often powered off overnight. If the run is missed, it should happen soon after the next boot. Which systemd timmediumLinux5 XP	Linux	New	medium	5
Booting into Rescue ModeAfter a bad change, a service hangs the boot. You have console access and the root password. How do you boot once into single-user rescue mode without changing mediumLinux5 XP	Linux	New	medium	5
Keeping Logs Across RebootsA server rebooted unexpectedly. journalctl --list-boots shows only the current boot, so the logs from before the crash are gone. journald.conf has the default SmediumLinux5 XP	Linux	New	medium	5
Filtering the JournalYou need only errors or worse from the SSH service in the last hour. Which command gives that?easyLinux3 XP	Linux	New	easy	3
Which Package Owns a FileOn a RHEL server you find /usr/bin/dig and want to know which installed package it came from. Which command answers that?easyLinux3 XP	Linux	New	easy	3
Persistent Static IP with nmcliYou set a server's address with ip addr add 10.0.5.20/24 dev ens3. It works, but after a reboot the address is gone. The connection profile is named ens3. How dmediumLinux5 XP	Linux	New	medium	5
Password Aging with chageNew user maria must change her password at first login, and from then on every 90 days. Which commands do this?easyLinux3 XP	Linux	New	easy	3
Loading Kernel ModulesYou need to load the vfiopci kernel module, which depends on other modules that are not loaded yet. Which command handles the dependencies for you?easyLinux3 XP	Linux	New	easy	3
autofs Indirect MapsYou configured autofs for NFS. /etc/auto.master.d/shares.autofs contains /shares /etc/auto.shares, and /etc/auto.shares contains data -rw,sync nfs1:/export/datahardLinux8 XP	Linux	New	hard	8
Process Priority with niceA regular user starts a long compression job with nice -n 10 xz big.tar, then tries to speed it up with renice -n 0 -p <pid>. The command fails with Permission easyLinux3 XP	Linux	New	easy	3