AIX-to-Linux Quick Start Comparison Modified from a more-complete UNIXguide.net page.

Man Pages Directory Mappings User Accounts General Commands Printers TCP/IP System Files LVM Commands Miscellaneous Commands Software Devices AFS Other References

Directory Mappings AIX RedHat Linux

Root File System / /dev/hd4 / /dev/sda2 if SCSI /dev/hda2 if IDE

Home Directories /home /dev/hd1 /home is in Root File System O.S. Executables /usr /dev/hd2 /usr is in Root File System Temporary Space /tmp /dev/hd3 /tmp is in Root File System System Variable Data /var /dev/hd9var /var is in Root File System

Boot /dev/hd5 /boot /dev/sda1 if SCSI /dev/hda1 if IDE

Paging Logical Volume type="paging" Partition Id=82="Linux swap"

See also the Filesystem Hierachy Standard (FHS) for a fuller discussion of the "proper" UNIX file system hierarchy.

Linux has three sets of apparently duplicate directories; /bin & /usr/bin, /sbin & /usr/sbin, and /lib & /usr/lib. This can be a source of confusion. Under AIX for example, ksh is the default shell and it's normal to see #!/usr/bin/ksh in the first line of a ksh script. Under Linux, bash (the Bourne-Again Shell) is the default shell and ksh is NOT in /usr/bin/ksh, leading one to believe Linux does not have ksh. Not true. Under Linux, ksh is at /bin/ksh. (Actually, since /bin is a link to /usr/bin under AIX, ksh is also at /bin/ksh, so to make bilinugual scripts, #!/bin/ksh is best.)

The reason for these apparently duplicate directories is, in the initial boot phases or when Linux boots into single-user mode (which is the same thing), only the root file system is mounted. It's true that by default, /usr is in the root file system, but it may not be. It might be configured in its own partition or even NFS mounted from another machine in R/O mode. Given this, everything needed to boot Linux or will be needed to repair a broken system,

needs to be in the root file system. Yet to keep the root file system as small as possible, all non-essential files are kept under /usr.

This is also why they say that those 5 directories (/bin, /sbin, /etc, /dev, and /lib) must be in the root partition.

User Accounts AIX RedHat Linux

Password Files /etc/passwd /etc/security/passwd

/etc/passwd /etc/shadow

Allow/Deny root's Remote telnet Login

rlogin=true in /etc/security/user stanza

Comment out securetty line in /etc/pam.d/login

Recover root's Password

Boot from CD or Tape, Installation/Maintenance Start Limited Shell getrootfs hdisk0 vi /etc/security/passwd

At grub boot loader screen, press "e" to edit, select "kernel" line press "e" to edit, Add " s" at end of line press <Enter> to accept changes, press "b" to boot, at shell prompt, passwd root

Create new user mkuser useradd Delete user rmuser userdel

Default User Group

staff=Group ID 1

The same as their userid, both name and number. E.G. User Name=jasper, User ID=10167, Group Name=jasper, Group ID=10167

General Commands AIX RedHat Linux

Absolute Path tar tar cvf foo.tar /etc/passwd tar Pcvf foo.tar /etc/passwd

ping Broadcast Address

ping -c 1 10.224.88.255 ping -b -c 1 10.224.88.255

Admin Helpers smit or smitty 41 redhat-config-* programs in /usr/sbin & /usr/bin

Performance Monitor

top lsof monitor

top lsof

System Activity Reporter

sar sar sysstat

I/O Statistics iostat iostat sysstat

Boot-Time Error Log

alog -o -t boot dmesg

Display Swap Size lsps -a free

Printers AIX RedHat Linux Printer Queues /etc/qconfig /var/spool/lpd/lp/*

Control Print Server Daemon startsrc -s lpd stopsrc -s lpd lssrc -s lpd

service cups start service cups stop service cups status

Submit Print Jobs enq lp lpr qprt

lpr

LP Statistics enq -A lpq lpstat qchk

lpq

Remove Print Jobs cancel lprm qcan enq -x

lprm

Add Printer Queue smit mkpq redhat-config-printer printtool

Remove Printer Queue smit rmpq

Default Printer First Stanza in /etc/qconfig export LPDEST="pq"

TCP/IP AIX RedHat Linux Network IP Configuration

lsattr -E -l inet0 /etc/sysconfig/network-scripts/ifcfg-eth*

Name Service Switch

/etc/netsvc.conf /etc/nsswitch.conf

Network Parameters no -a sysctl -a | grep net Secondary IP Address

ifconfig en0 alias w.x.y.z

modprobe ip_alias ifconfig eth0:1 w.x.y.z

Login Prompt/Herald

/etc/security/login.cfg /etc/issue

System Files AIX RedHat Linux NFS Client Mounted Directories /etc/xtab /var/lib/nfs/xtab Max File System Size 128 GB 2 TB

Max File Size 64 GB 2 GB (512-byte block size) 8192 GB (8-KB block size)

LVM Commands AIX RedHat Linux

Filesystem Table /etc/filesystems /etc/fstab Device Listing lsdev -C cat /proc/devices

Disk Information bootinfo -s hdisk# cat /proc/scsi/scsi0/sda/model

LVM Concepts Partition Logical Extents Volume Logical Volume

Journal File System Type jfs ext3 reiserfs

Default Volume Group /dev/rootvg None Display Volume Group lsvg -l rootvg vgdisplay -v Modify Physical Volume chpv pvchange

Prepare Physical Disk mkdev -c disk -l hdisk# pvcreate

List Physical Volume lspv pvdisplay Remove disk from volume group

reducevg vgreduce

Move logical volumes to another physical volumes

migratepv pvmove

Create volume group mkvg vgcreate

Remove Volume Group varyoffvg exportvg vgremove

Volume Group Availability chvg varyonvg varyoffvg

vgchange

Restore Volume Group importvg vgcfgrestore Export/Import Volume Group exportvg/importvg vgexport/vgimport List Volume Groups lsvg vgscan Change Logical Volume Characteristics

chlv lvchange

List Logical Volumes lslv lvdisplay Make Logical Volume mklv lvcreate Extend Logical Volume extendlv lvextend

Reduce Logical Volume AIX Reduce LV Procedure

lvreduce

Remove Logical Volume rmlv lvremove

Prepare Boot Volumes bootlist -m normal grub-install /dev/sda2 if SCSI grub-install /dev/hda2 if IDE

Extend File System chfs -a size=# fs-name (# is 512-byte blocks)

resize2fs

Reduce/Split Mirrors rmlvcopy lvsplit Merge Mirrors lvmerge Create Mirrors mklv -c 2 Add Mirrors mklvcopy lv 2

Create Striped Volumes mklv -u 3 -S 64K lvcreate -i 3 -I 64 System Recovery Tape mksysb -i /dev/rmt0 Backup savevg -i rootvg tar cvf /dev/rst0 / Restore restvg tar xvf /dev/rst0

Miscellaneous Commands AIX RedHat Linux

Startup script /etc/rc /etc/rc.d/rc

Kernel /usr/lib/boot/unix_up /boot/vmlinuz (compressed) /boot/vmlinux (uncompressed)

Kernel Parameters lsattr -E -l sys0 no -a sysctl -a

Reconfigure the Kernel

chdev -l sys0 -a

cd /usr/src/linux make mrproper make menuconfig make dep make clean make bzImage make install make modules make modules_install cp arch/i386/boot/bzImage /boot/vmlinuz-2.2.16 cd /boot mv initrd-2.4.21-20.ELsmp initrd-2.4.21-20.ELsmp.save mkinitrd initrd-2.4.21-20.ELsmp $(uname -r) vi /boot/grub/grub.conf

List modules genkex lsmod Load module insmod Unload module rmmod Initialize System install_assist netconf Physical RAM bootinfo -r free Kernel Bits bootinfo -K getconf WORD_BIT Crash Utility crash lcrash

Trace System Calls syscalls strace OS Level oslevel uname -r Run Level who -r runlevel Tape Control tctl mt Core Dump Files /var/adm/ras Timezone Management

/etc/environment /etc/profile /etc/sysconfig/clock

NTP Daemon /etc/ntp.conf startsrc -s xntpd stopsrc -s xntpd lssrc -s xntpd

/etc/ntp.conf service xntpd start service ntpd stop service ntpd status

Software AIX RedHat Linux Install Software installp -a rpm -i package Uninstall Software

installp -u rpm -e package

List Installed Software

lslpp -L all rpm -qa

Verify Installed Software

lppchk -v rpm -V package

List Files lslpp -f fileset rpm -ql package

List Installed Patches

instfix -i

Package Owner lslpp -w path rpm -qf file

SW Directory /usr/lpp /var/lib/rpm

Rescan SCSI Bus

cfgmgr

echo "scsi add-single-device 0 1 2 3" > /proc/scsi/scsi will reprobe for a single device only on Card 0, Channel 1, Device 2, Lun 3, and add it if it is found

Devices AIX RedHat Linux Install Devices cfgmgr -v /dev/MAKEDEV Remove Device rmdev -l Device Drivers lscfg CPU lsdev -Cc processor cat /proc/cpuinfo List Terminal lsdev -Cc tty

Diagnostics diag lspci pnpdump

Whole Disk /dev/hdisk# /dev/sda CDROM /dev/cd0 /dev/cdrom CDROM File System Type cdrfs iso9660 Rewinding Tape Drive /dev/rmt0 /dev/rst0 { c 9 0} Non-rewinding Tape Drive /dev/rmt0.1 /dev/nrst0 { c 9 128 } Floppy Drive /dev/rfd0 /dev/fd0

AFS AIX RedHat Linux Code Source

IBM Transarc's Lab www.openafs.org

AFS Cache Should be defined as Same.

/usr/vice/cache

its own file system before installing AFS. 100MB is minimum. 1GB is better.

Install Directions

cd /tmp ftp jasper cd /afs/d/software/base/AFS_3.6 get afsinstall.sh get afsclient-42.tar quit chmod +x afsinstall.sh ./afsinstall.sh afsclient-42.tar rm afsinstall.sh afsclient-42.tar

mkdir /tmp/afs cd /tmp/afs scp -p jasper@jasper:/afs/d/software/base/linux/openafs-1.2.11/* . rpm -ivh *rpm vi /usr/vice/etc/cacheinfo and set the cache size to 95% of the number of 1K blocks of /usr/vice/cache. 95% of 1GB (my standard), is 953850. vi /usr/vice/etc/ThisCell set the cell name to delphion.com. vi /usr/vice/etc/CellServDB replace all existing lines with >delphion.com # Thomson-Delphion 10.224.88.241 #afs1.delphion.com To start AFS, service afs start To allow AFS-authenticated logins, ftp's, etc, cd /etc/pam.d cp -p system-auth system-auth.Before.AFS cp -p --reply=yes /tmp/afs/system-auth system-auth rm -rf /tmp/afs

@sys (fs sysname)

rs_aix42 i386_linux24

Delphion-Standard Links

/local -> /afs/d/@sys/local /u -> /afs/d/u /usr/afsws -> /afs/d/@sys/usr/afsws

/local -> /afs/d/@sys/local /u -> /afs/d/u

Other References AIX RedHat Linux FAQ AIX-FAQ Linux FAQ

Online Manual AIX 4.3 Books Linux Documentation Project

Technical Support RS/6000 TechSupport Red Hat support

Phone Number 1-800-CALL-AIX 1-888-REDHAT1 Free Software Bull Linux Software Map

Certification www.ibm.com RHCT & RHCE