Module 8 - Process Management

1.Linux boot loader 2.Linux boot process 3.Linux processes 4.Linux services 5.Linux top 6.Remember proc ? 7.Linux Device Management 8.Linux Massages log 9.Schedule tasks with cron Process Management

/boot directory How to configure the grub boot loader using grub.conf Linux boot loader

the init process and the boot flow Linux run levels /etc/init.d the init command changing default run level /etc/inittab Booting into single mode from the boot-loader menu Linux boot process

Find a process with ps # ps aux # ps –ef Kill a process with kill # kill -15 PID # kill -9 PID Linux processes

System-V Scripts The Init directories rc.local The chkconfig command Linux services

top free the /proc directory Linux Top

dmesg kudzu lsmod lspci lsusb Linux Device Management

/var/log/massages is the main kernel log Jul 7 14:20:59 NX102 kernel: iscsi: registered transport (be2iscsi) Jul 7 14:20:59 NX102 kernel: ADDRCONF(NETDEV_UP): eth0: link is not ready Jul 7 14:20:59 NX102 kernel: 8021q: adding VLAN 0 to HW filter on device eth0 Jul 7 14:20:59 NX102 kernel: e1000: eth0 NIC Link is Up 1000 Mbps Full Duplex, Flow Control Jul 7 14:20:59 NX102 kernel: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready Jul 7 14:20:59 NX102 kernel: scsi1 : iSCSI Initiator over TCP/IP Linux Massages log

Schedule tasks with cron

# crontab -l # crontab -e * * * /home/ilanit/ort.sh > /dev/null 2>&1 cron daemon

1.Go to run level 3 2.Find your current run level 3.set your default init to 3 4.reboot and enter single mode, then change the run level back to 5. 5.Open a firefox browser, find the browser PID and kill it gently. 6.find all the services set to run in run level 5 7.set the cups server to start at all relevant levels 8.set the linux firewall not to start at all run levels Exercise

9.create a new title in the boot loader and call it Linux-Your-Name 10. Set this to be the default title. 11. Set the boot loader count down to 10 seconds 12. Add a new Virtual Hard Drive (1GB) to the VirtualBox Linux guest. 13. Reboot and check with dmesg to locate this new disk. 14.Create a cron job that will run every day at 12:30 past midnight (AM) and will look for files with 777 perm and save a list of the files under /tmp Exercise

15. Create a list of all linux usb and pci devices. 16. issue the lsmod mode and examine the output, do you see the Bluetooth driver loaded ? 17. what is this file ? # /etc/sysconfig/hwconf 18. Can you manually run kudzu ? 19. How many processes are currently running ? 20. Open 6 firefox browsers. can you kill them all In one single command ? 21. How can you count the linux cpu cores in one command ?

cat /proc/cpuinfo | grep -i cores | tr -s " " | awk '{print $4}' | wc -m