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dave spink toolset

LINUX COMMANDS:
PACKAGES	SERVICES	NFS	IN USE
FILE SYSTEMS	FILES	CONFIGS	MISC

PACKAGES
ls /var/lib/rpm	;database directory for installed rpms
ls /var/lib/dpkg	;databasae directory for installed for debian with apt-get
rpm --rebuilddb	;after upgrading RPM program you may need to rebuild rpm database
rpm -Uvh bind.x86_64	;install or upgrade bind
yum repolist	;OEL and RHEL7 are based on Fedora which uses yum.
yum list	;list of all packages in all repos
yum list installed	;packages installed
yum update	;update all packages
yum info httpd.x86_64	;package info
yum install httpd.x86_64	;install apache web server
yum remove httpd.x86_64	;remove package
apt-get update	;debian uses apt-get for automated installation of packages

SERVICES
service nfs restart	;systemd replaces sysvinit, and services now call systemctl commands
systemctl list-unit-files	;list all units - devices, mounts, paths, servies, sockets
systemctl list-units --type service	;list a specific unit
systemctl restart nfs.service	;restart nfs
systemctl status nfs	;service status
systemctl enable firewalld.service	;enable service
systemctl start firewalld.service	;start service
systemctl stop firewalld.service	;stop service
systemctl disable firewalld.service	;disable service

NFS CHECK
cat /etc/exports	;see NFS shares
nfsstat -c	;client stats, check retrans, badcalls
nfsstat -s	;server stats
nfsstat -m	;stats for each file system, check srtt round trip times
pgrep nfsd	;get process ID for stack trace
strace -p 243	;trace process
rpcinfo -u servername mountd	;check NFS server is responding to RPC requests
netstat -rn	;checking routing table
showmount -a	;see what servers are accessing the NFS shares
showmount -e	;see list of NFS shares


IN USE
free	;includes total RAM, buffers, cache, swap
ps u U spi0004	;display extra process information for user
top	;use "r" to change process priority, "k" to kill
sar 1 5	;five samples one second apart
nice -n 12 xterm	;set run priority from default 0 to 10, range -20 to 19
renice 0 14030	;change run priority on a active process
killall -i xterm	;interactive kill all
netstat -ap	;show listening and nonlistening sockets with PID
uptime	;plus load average over 1, 5 and 15 minute interval
cat /proc/interrupts	;see interrupts in use
tcpdump -q	;used in linux like snoop, docs in /usr/local/doc/tcpdump
strace -p 28218	;see what the process is actually doing

FILE SYSTEMS
fdisk /dev/sdb	;partition tool
fdisk /dev/sdb -l	;list partition table
mkfs -V -t ext3 /dev/sdb1	;a front end to create file systems, this calls mkfs.ext3
mkfs.ext3 -j -v /dev/sdb1	;also known as mke2fs
fsck -t ext3 /dev/sdb1	;on run on mounted read only or umounted file systems
fsck.ext3 -f /dev/sdb2	;also known as e2fsck, -f force a check
mount -a	;mount all file systems in /etc/fstab
mount -t ext3 /dev/sdb1 /backup	;mount file system
mount -t cifs -o username=adcpscorp/dspink //tpawindowsdev/temp /test	;mount Windows share on Linux
mount -t cifs -o username=spi0004 //d1de0199/docs /test	;mount Linux samba share on Linux
cat /etc/mtab	;see mounted file systems

FILES
df -l	;ignore network filesystems
df -hT	;display file system type and usage in GB
ls -p	;appends indicator code to show type of file
cp -u fileA fileB	;only copy if fileA is newer than fileB
ln /usr/testprog mylink	;hard link - ln source link
find ./ -maxdepth 1 -name gtypist-2.7.tar.gz	;limit number of subdirectories to search
find / -uid 501	;find all files with UID 501
find / -perm /2000	;find all files with SUID bits set
locate yum	;like find, but searches a database updated by updatebd
updatedb	;updates located database, normally forms part of cron
whereis samba	;searches in standard certain locations
whatis samba	;searches whatis database for words
chgrp sapusers myfile	;change group ownership for this file
setfacl -m user:spi0004:r-- myfile.txt	;-m set an ACL, requires acl mount option in /etc/fstab
getfacl myfile.txt	;see ACLs on a file
logrotate	;rotate log files
su -c "rm -rf /tmp*"	;remove all files first prompting for root password
dd if=/dev/zero of=/shareX/testfile.out bs=1MB count=1000000	;create file 1MB IOs
dd if=/shareX/testfile.out of=/dev/null bs=128K count=1000000	;read file 128KB chunks

CONFIGS
/usr/lib/systemd/systemd	;in RHEL7 /sbin/init is now a symbolic link to /usr/lib/systemd/system
cat /etc/systemd/system/default.target	;in RHEL7 the direction for booting depends on default.target
cd /etc/systemd/system/multi-user.target.wants	;see symlinks to services started
cat /etc/nsswitch.conf	;search order
cd /etc/sysconfig/network-scripts	;see ifcfg-eth0
route add default gw 10.152.30.1	;add default route
route add -net 10.152.30.0 netmask 255.255.254.0 gw 10.152.30.1	;add route with gateway
route add -net 169.254.0.0 netmask 255.255.0.0 dev eth0	;add route
route del -net 169.254.0.0 netmask 255.255.0.0 dev eth0	;delete route
echo "1" > /proc/sys/net/ipv4/ip_forward	;configure linux as router
vi /etc/sysctl.conf	;see net.ipv4.ip_forward = 0

MISC
journalctl -k	;see kernel messages from current boot
cat /etc/crontab	;display system crontab
tail -f /var/log/cron	;cron log
cat /var/spool/cron/root	;see cron entries created by user root
at -f mycmds.txt noon	;run job with commands in file at noon
atq	;see queued jobs
Ctrl+A	;moves cursor to start of line
Ctrl+E	;moves cursor to end of line
info	;newer version of man pages
export PATH=$PATH:/usr/local/bin	;bash set environment variable
setenv PATH "${PATH}:/usr/local/bin"	;tcsh set environment variable
Samba
cat /etc/samba/smbpasswd	;see contents of samba file
smbpasswd -a drstemp	;add user to samba password file
smbpasswd -x drstemp	;delete user from samba password file
mount -t cifs -o username=adcpscorp/dspink //tpawindowsdev/temp /test	;mount Windows share on Linux
mount -t cifs -o username=spi0004 //d1de0199/docs /test	;mount Linux samba share on Linux
smbclient -L d1de0199	;see list of available shares
smbclient //d1de0102/docs	;gives ftp like commands i.e. after logging in
nmblookup -U 10.152.20.140 tpaexbe02n1	;queries WINS database, like nslookup on DNS
IP Tables
iptables -L -t filter	;see filter table (other tables are nat and mangle)
iptables -t filter -F FORWARD	;flush all rules in FORWARD chain
iptables -t filter -F FORWARD DROP	;flush rules and set default policy to DROP
iptables -A INPUT -p udp --sport 53 -j ACCEPT	;let DNS traffic
iptables -A OUTPUT -p udp --dport 53 -j ACCEPT	;let DNS traffic

LINUX COMMANDS: