Linux sistemlerinde belli bir kullanıcıya ait, belli dosyaları silme (Yeni başlayanlar için :) )

Bir kullanıcıya ait sonu tmp ile biten dosyaları silmek için find komutunu kullanabiliriz.

Örnek;

find /home -uid 32768 -name \*.tmp -exec rm -f {} \; -print

kendi kullanıcınızın id si ile 32768 değiştirmeyi unutmayınız.

Detaylı bilgi için: man find

Common administrative commands in Red Hat Enterprise Linux 5, 6, and 7 - from Redhat

https://access.redhat.com/articles/1189123

System basics

Task	RHEL5	RHEL6	RHEL7
View subscription information	/etc/sysconfig/rhn/systemid	/etc/sysconfig/rhn/systemid subscription-manager identity	subscription-manager identity
Configure subscription	rhn_register subscription-manager 1	rhn_register rhnreg_ks subscription-manager	subscription-manager2 rhn_register 3
View RHEL version information	/etc/redhat-release
View system profile	sosreport dmidecode hwbrowser	sosreport dmidecode lstopo lscpu

Basic configuration

Task	RHEL5	RHEL6	RHEL7
Graphical configuration tools	system-config-*		gnome-control-center
Text-based configuration tools	system-config-*-tui
Configure printer	system-config-printer
Configure network	system-config-network		nmcli nmtui nm-connection-editor
Configure system language	system-config-language		localectl
Configure time and date	system-config-date date		timedatectl date
Synchronize time and date	ntpdate /etc/ntp.conf		timedatectl /etc/chrony.conf ntpdate
Configure keyboard	system-config-keyboard		localectl
Configure SSH	/etc/ssh/ssh_config /etc/ssh/sshd_config ~/.ssh/config ssh-keygen

Jobs and services

Task	RHEL5	RHEL6	RHEL7
List all services	chkconfig --list ls /etc/init.d/		systemctl -at service ls /etc/systemd/system/*.service ls /usr/lib/systemd/system/*.service
List running services	service --status-all		systemctl -t service --state=active
Start/stop service	service name start service name stop		systemctl start name.service systemctl stop name.service
Enable/disable service	chkconfig name on chkconfig name off		systemctl enable name.service systemctl disable name.service
View service status	service name status		systemctl status name.service
Check if service is enabled	chkconfig name --list		systemctl is-enabled name
Create new service file or modify configuration	chkconfig --add		systemctl daemon-reload /etc/systemd/system/*.service
View run level/target	runlevel who -r		systemctl get-default who -r
Change run level/target	/etc/inittab init run_level		systemctl isolate name.target systemctl set-default
Configure logging	/etc/syslog.conf	/etc/rsyslog.conf	/etc/rsyslog.conf /etc/rsyslog.d/*.conf /var/log/journal systemd-journald.service
View logs	/var/log		/var/log journalctl
Configure system audit	add audit=1 to kernel cmdline auditctl /etc/audit/auditd.conf /etc/audit/audit.rules authconfig /etc/pam.d/system-auth pam_tty_audit kernel module
View audit output	aureport /var/log/faillog
Schedule/batch tasks	cron at batch
Find file by name	locate
Find file by characteristic	find
Create archive	tar cpio zip

Kernel, boot, and hardware

Task	RHEL5	RHEL6	RHEL7
Single user/rescue mode	append 1 or s or init=/bin/bash to kernel cmdline		append rd.break or init=/bin/bash to kernel cmdline
Shut down system	shutdown
Power off system	poweroff		poweroff systemctl poweroff
Halt system	halt		halt systemctl halt
Reboot system	reboot		reboot systemctl reboot
Configure default run level/target	/etc/inittab		systemctl set-default
Configure GRUB bootloader	/boot/grub/grub.conf		/etc/default/grub grub2-mkconfig grub-set-default
Configure kernel module	modprobe
View hardware configured	hwbrowser	lshw (in EPEL)
Configure hardware device	udev
View kernel parameters	sysctl -a cat /proc/cmdline
Load kernel module	modprobe
Remove kernel module	modprobe -r
View kernel version	rpm -q kernel uname -r

Software management

Task	RHEL5	RHEL6	RHEL7
Install software	yum install yum groupinstall		yum install yum group install
View software info	yum info yum groupinfo		yum info yum group info
Update software	yum update
Upgrade software	yum upgrade
Configure software repository	subscription-manager repos /etc/yum.repos.d/*.repo
Find package owning file	rpm -qf filename yum provides filename-glob
View software version	rpm -q packagename
View installed software	rpm -qa yum list installed

User management

Task	RHEL5	RHEL6	RHEL7
Graphical user management	system-config-users
Create user account	useradd
Delete user account	userdel
View/change user account details	usermod /etc/passwd vipw id
Create user group	groupadd
Delete user group	groupdel
Change group details	groupmod /etc/group
Change user password	passwd
Change user permissions	usermod visudo
Change group permissions	groupmod visudo
Change password policy	chage
View user sessions	w

File systems, volumes, and disks

Task	RHEL5	RHEL6	RHEL7
Default file system	ext3	ext4	xfs
Create/modify disk partitions	fdisk parted		fdisk gdisk parted ssm create
Format disk partition	mkfs.filesystem_type (ext4, xfs) mkswap		mkfs.filesystem_type (ext4, xfs) mkswap ssm create
Defragment disk space	copy data to new file system fsck (look for 'non-contiguous inodes')	copy data to new file system fsck (look for 'non-contiguous inodes') xfs_fsr
Mount storage	mount /etc/fstab		mount /etc/fstab ssm mount
Mount and activate swap	/etc/fstab swapon -a
Configure static mounts	/etc/fstab
View free disk space	df
View logical volume info	lvdisplay lvs vgdisplay vgs pvdisplay pvs
Create physical volume	pvcreate		pvcreate ssm create (if backend is lvm)
Create volume group	vgcreate		vgcreate ssm create (if backend is lvm)
Create logical volume	lvcreate		lvcreate ssm create (if backend is lvm)
Enlarge volumes formatted with default file system	vgextend lvextend resize2fs		vgextend lvextend xfs_growfs ssm resize
Shrink volumes formatted with default file system	resize2fs lvreduce vgreduce		XFS cannot currently be shrunk; copy desired data to a smaller file system.
Check/repair file system	fsck		fsck ssm check
View NFS share	showmount -e mount
Configure NFS share	/etc/exports service nfs reload		/etc/exports systemctl reload nfs.service
Configure on-demand auto-mounts	/etc/auto.master.d/*.autofs /etc/auto.*
Change file permissions	chmod chown chgrp umask (future file creation)
Change file attributes	chattr
Change access control list	setfacl

Networking

Task	RHEL5	RHEL6	RHEL7
Configure name resolution	/etc/hosts /etc/resolv.conf		/etc/hosts /etc/resolv.conf nmcli con mod
Configure hostname	/etc/sysconfig/network		hostnamectl /etc/hostname nmtui
View network interface info	ip addr ifconfig brctl		ip addr nmcli dev show teamdctl brctl bridge
Configure network interface	/etc/sysconfig/network-scripts/ifcfg-*		/etc/sysconfig/network-scripts/ifcfg-* nmcli con [add|mod|edit] nmtui nm-connection-editor
View routes	ip route
Configure routes	ip route add system-config-network /etc/sysconfig/route-iface		ip route add nmcli nmtui nm-connection-editor /etc/sysconfig/route-iface
Configure firewall	iptables and ip6tables /etc/sysconfig/ip*tables	iptables and ip6tables /etc/sysconfig/ip*tables system-config-firewall	firewall-cmd firewall-config
View ports/sockets	ss lsof netstat		ss lsof

Security and identity

Task	RHEL5	RHEL6	RHEL7
Configure system security	/etc/selinux/config chcon restorecon semanage setsebool system-config-selinux
Report on system security	sealert
LDAP, SSSD, Kerberos	authconfig authconfig-tui authconfig-gtk
Network users	getent

Resource management

Task	RHEL5	RHEL6	RHEL7
Trace system calls	strace
Trace library calls	ltrace
Change process priority	nice renice
Change process run location	taskset
Kill a process	kill pkill killall
View system usage	top ps sar iostat netstat vmstat mpstat numastat	top ps sar iostat netstat ss vmstat mpstat numastat tuna	top ps sar iostat ss vmstat mpstat numastat tuna
View disk usage	df	df iostat

Günün linki

http://w.on24.com/r.htm?e=1034198&s=1&k=7E5E75022521CC34F2F126A3BFF68C88&partnerref=ON24

lvm i hızlandırmak (Gazlamak :) ) { SSD diski cache disk olarak kullanmak md_cache}

Linux dağıtımlarından her hangi birinde, softraid ve lvm kullanıyorsanız, performansınız düşüklüğünden şikayetçi iseniz, bir adet ssd disk + lvmcache  yardımınıza koşacaktır. lvmcache güncel linux dağıtımlarında standart bulunmaktadır.

Kullandığınız dağıtımda bu özelliğin olup olmadığını öğrenmek için;

                     #modinfo dm_cache

komutundan faydalanabilirsiniz.


Bu komut sizlere aşağıdaki gibi bir çıktı veriyorsa sorun yok.

root@ultra27:~# modinfo dm_cache
filename:       /lib/modules/4.2.0-10-generic/kernel/drivers/md/dm-cache.ko
license:        GPL
author:         Joe Thornber <ejt@redhat.com>
description:    device-mapper cache target
srcversion:     5B4207739B7A6C60B2A22CE
depends:        dm-persistent-data,dm-bio-prison
intree:         Y
vermagic:       4.2.0-10-generic SMP mod_unload modversions
signer:         Build time autogenerated kernel key
sig_key:        F3:83:3C:CF:74:C7:88:F8:B9:EC:CF:4D:A2:19:C0:B6:39:84:EE:58
sig_hashalgo:   sha512
parm:           cache_copy_throttle:A percentage of time allocated for copying to and/or from cache (uint)
root@ultra27:~#

Şayet sisteminizde mevcut değilse sisteminizi/kernelinizi güncellemeniz yeterli olur.

dm_cache kullanılan sistemde lvs çıktısı;

Kullanımını;
                  man lvmcache
ile öğrenebilirsiniz. Yok ben man den öğrenemiyorum diyenlerdenseniz;


Unutmamak gereken önemli nokta, cache olarak kaliteli ssd kullanılması gerektiği.  ssd diskinizden emin değilseniz, 2 tane ssd yi mirror olarak kullanabilirsiniz.

Kendim ssd cache olarak "Intel SSD DC S3700 Series 100GB, SATA" disklerinden kullanıyorum.

    Model Number:       INTEL SSDSC2BA100G3                    
    Firmware Revision:  5DV10270

Sizlerede tavsiye ederim.

 

uzun bir aranın ardından biraz yenilik iyi olur diyerek tekrardan linux lvm cache kullanmaya başladım. Başlamışkenden bu bilgiyi hatırlamak için tahtaya yazıyorum.

Kişisel lab ortamlarında kullanabilirsiniz. 

Sistem disklerimiz;

Data diskimiz : /dev/sda                (normal sata 3.5" disk)

Cache diskimiz : /dev/sdb

                              /dev/sdc

Cache metadata diskimiz:   /dev/nvme0n1p3

                                                 /dev/nvme1n1p3                      

lvmcache cachemetada data için en fazla 16GB destekler, buda fazlasıyla yeterli.

cache metadatayı nvme diskimiz  üzerinde, cache olarak ssd sata diskimizi, data diskimiz olarak normal sata diski kullanıyoruz. ufacık milyonlarca dosyanız varsa metadatayı yüksek tutabiliriz.

Hadi başlayalım.

    1. Volum grubu oluşturuyoruz

         # vgcreate vg_data /dev/sd[abc} /dev/nvme0n1p3 /dev/nvme1n1p3

    2. Data lv yi oluşturuyoruz

        lvcreate -L16T -n lv_data vg_data /dev/sda

    3. Cache lv yi oluşturalım

        # lvcreate -L1T -i2 -n lv_cache vg_data /dev/sdb /dev/sdc

    4. Cache meta datayı oluşturalım

       # lvcreta -L16G -i2 -n lv_cachemetadata vg_data /dev/nvme0n1p3 /dev/nvme1n1p3 

    5. cache pool olarak ayarlayalım

       # lvconvert --type cache-pool --poolmetadata vg_data/lv_cachemetadata vg_data/lv_cache

    6. Kontrol edelim

         # lvs

         # lvs -a -o +devices vg_data

 

sparc sistemlerde boot diski seçmek

reset
reset-all
probe-scsi-all

{0} ok devalias
ttya                     /ebus@c0/serial@0,ca0000
nvram                    /virtual-devices/nvram@3
net3                     /pci@0/pci@0/pci@1/pci@0/pci@3/network@0,1
net2                     /pci@0/pci@0/pci@1/pci@0/pci@3/network@0
net1                     /pci@0/pci@0/pci@1/pci@0/pci@2/network@0,1
net0                     /pci@0/pci@0/pci@1/pci@0/pci@2/network@0
net                      /pci@0/pci@0/pci@1/pci@0/pci@2/network@0
cdrom                    /pci@0/pci@0/pci@1/pci@0/pci@1/pci@0/usb@0,2/storage@2/disk@0:f
disk7                    /pci@0/pci@0/pci@2/scsi@0/disk@7
disk6                    /pci@0/pci@0/pci@2/scsi@0/disk@6
disk5                    /pci@0/pci@0/pci@2/scsi@0/disk@5
disk4                    /pci@0/pci@0/pci@2/scsi@0/disk@4
disk3                    /pci@0/pci@0/pci@2/scsi@0/disk@3
disk2                    /pci@0/pci@0/pci@2/scsi@0/disk@2
disk1                    /pci@0/pci@0/pci@2/scsi@0/disk@1
disk0                    /pci@0/pci@0/pci@2/scsi@0/disk@0
disk                     /pci@0/pci@0/pci@2/scsi@0/disk@0
scsi                     /pci@0/pci@0/pci@2/scsi@0
virtual-console          /virtual-devices/console@1
name                     aliases
{0} ok set boot-device /pci@0/pci@0/pci@2/scsi@0/disk@4
Unimplemented action # 1 on object (f02733b0) , whose maximum action # is -1

{0} ok setenv boot-device /pci@0/pci@0/pci@2/scsi@0/disk@4
boot-device =           /pci@0/pci@0/pci@2/scsi@0/disk@4
{0} ok boot
Boot device: /pci@0/pci@0/pci@2/scsi@0/disk@4  File and args:


 {0} ok show-disks

Bildiğimizi zannettiğimiz, kulaktan dolma bilgilerle...

Merhabalar,

Bu gün bir soruya cevap verirken, düşünmeden, araştırmadan, hızlıca cevap verdiğimizi fark ettim.

 "Linux, Microsoft Windows 7 Nedir? Aralarındaki temel farkı tek cümle ile özetleyiniz." sorusuna 55 den fazla cevap  içerisinde tane bile doğru cevap çıkmaması.

55 tane cevap veren farklı insanlardan hiç birisi,  arama motorlarına(google/yandex vs.)  "linux nedir"  sorusunu sormamış olması çok ilginç.

Galiba bu bizim toplumsal yapımızı gösteriyor..



Cevabı merak edip, araştırmayan için cevap;

Linux  kernel(işletim sistemleri için), microsoft windows 7 ise işletim sistemidir.

Redhat/Debian/Suse gibi dağıtımları işletim sistemi olarak kabul edebiliriz.

freebsd ve qmail meraklıları için

Merhabalar,

üzerinden çıkalı yıllar geçsede önemini kaybetmeyen freebsd ve qmail kurulumu hakkında bir kaynağı paylaşmak istiyorum.

http://www.freebsdrocks.net/index.php/documents/17-qmail-2-0-testing-only

Umarım meraklılarına faydalı olur.