Slackware Linux Post-installation

assuming network configuration is already done

those steps are otherwise partly automated by the linuxconf script

Environment

Define a system-wide path (remove the user-specific part)

cp -pi /etc/profile /etc/profile.dist
vi /etc/profile

#MANPATH=/usr/local/man:/usr/local/share/man:/usr/man
PATH=/usr/local/bin:/usr/bin:/bin:/usr/local/sbin:/usr/sbin:/sbin
PATH=$PATH:/etc/rc.d:$HOME/bin
#PATH=$PATH:/usr/lib64/bcc:$HOME/xen

and at the end, enable the non-login shell parameters

#bash
source /etc/shrc

#ksh
#ENV=/etc/shrc

then rather create a system-wide shrc that will be forcibly linked against. This trick is required for non-login shells and so you X terminals also show up a nice prompt and aliases – think of GNU Screen.

vi /etc/shrc # new file

export MAKEFLAGS=-j$((`grep ^processor /proc/cpuinfo | tail -1 | awk '{print $3}'` + 1))

case "$-" in *i*)
    alias ll='ls --color=auto --group-directories-first -alh'
    alias ls='ls --color=auto --group-directories-first'
    alias psu='ps --pid 2 --ppid 2 --deselect ufw'
    alias cp='cp -i'
    alias mv='mv -i'
    alias rm='rm -i'

    alias runq='sendmail -q'
    alias diff='colordiff'

    alias clean="grep -vE '^[[:space:]]*(;|#|$)'"
    alias findexec='find . -executable -type f'
    alias lynx='lynx -accept_all_cookies'
    alias lynxg='lynx -accept_all_cookies https://www.google.com/ncr'
    alias irssi='echo did you forget to start gnu/screen or tmux?'
    alias ovs='ovs-vsctl'

    alias commit='git commit --allow-empty-message -m ""'
    alias commita='git commit -a --allow-empty-message -m ""'
    alias push='git commit --allow-empty-message -m "" && git push'
    alias pusha='git commit -a --allow-empty-message -m "" && git push'
    alias stat='git diff --stat --cached origin/master'
    alias pwgen='pwgen --capitalize --numerals --symbols --ambiguous 1$(( $RANDOM % 10 ))'

    warn="this is the host system - unalias if you are sure"
    alias shutdown="echo $warn"
    alias reboot="echo $warn"
    alias poweroff="echo $warn"
    alias halt="echo $warn"
    unset warn

    export TERM=xterm
    export EDITOR=/usr/bin/vi
    export MAIL=/var/mail/$USER
    export MAILCHECK=1
    /usr/bin/biff y
    w
    ;;
esac

some unused and unnecessary alternatives

    #export TERM=linux
    #export TERM=xterm-256color

    #alias wget='wget --ca-certificate=/etc/ssl/cacert.pem'
    #alias curl='curl --cacert /etc/ssl/cacert.pem'

    # Debian/Ubuntu fixup
    #export LC_ALL=en_US.UTF-8
    #export LANG=en_US.UTF-8
    #export LANGUAGE=en_US:en

also load the non-login shell parameters

ln -s ../etc/shrc ~/.bashrc

you can now apply it all at once

source /etc/profile

choose an editor

ls -lF /usr/bin/vi /usr/bin/elvis /usr/bin/vim
which vi

either keep the default NVI

–or– VIM

ln -sf vim /usr/bin/vi

–or– ELVIS

ln -sf elvis /usr/bin/vi

make sure Perl won’t piss you off about locales, at some point

slackpkg install glibc-2
perl -e exit

further tune for a multi-user system

removepkg sudo

chmod 700 /root/

prevent new users to get their own dedicated group

useradd -D -g users -s /bin/bash
cat /etc/default/useradd

mv -i /etc/login.defs /etc/login.defs.dist
grep -vE '^#|^$' /etc/login.defs.dist > /etc/login.defs.dist.clean
grep -vE '^#|^$' /etc/login.defs.dist > /etc/login.defs
cat >> /etc/login.defs <<-EOF

#USERGROUPS_ENAB yes
USERGROUPS_ENAB no
HOME_MODE 0700

EOF

the new default is +t for mail spool, hence no need to create anything there

vi /etc/default/useradd

#CREATE_MAIL_SPOOL=yes
CREATE_MAIL_SPOOL=no

you will probably need that one, some time in the future

ls -alF /usr/local/lib/
echo /usr/local/lib >> /etc/ld.so.conf
cat /etc/ld.so.conf
ldconfig

Daemons

Disable a few init scripts

cd /etc/rc.d/
#find . -executable -type f
ls -lF --color=auto

# REC or OPT
chmod -x rc.atd rc.bluetooth rc.fuse3 rc.inetd rc.wireless

you need to keep UDEV for PTY allocation

Are you clean?

netstat -lntup

Tune SSHD already.

Make sure there is a password in place, eventhough you might never use it (to prevent flawed services to authenticate as root without a password)

passwd

Packages & patching

See Packages and Patching

Miscellaneous

enable indexing

updatedb

fix defaults for git ($HOST short hostname is evaluated only if you have an FQDN, while $HOSTNAME always works)

echo $USER@${HOSTNAME%%\.*}
git config --global user.name  "$USER@${HOSTNAME%%\.*}"
git config --global user.email "$USER@${HOSTNAME%%\.*}"

can’t ask for /var/log/*/* because it would open too many files (/var/log/packages/*)

cat > /root/log <<-EOF
tail -n0 -F /var/log/* /var/log/xen/*.log'
EOF
chmod +x /root/log

get rid of unnecessary log MARKs

slackware 15+

vi /etc/default/syslogd

SYSLOGD_OPTS="-s -m0"

some issue that got fixed

# ls -lF /var/log/spooler
# grep missingok /etc/logrotate.d/syslog

apply and check

/etc/rc.d/rc.syslog restart
pgrep -a logd

SSL certificates

eventually harden your SSL certificates trust-store

Time zone

zone=Europe/Moscow

ls -lF /etc/localtime*
rm -f /etc/localtime*
ln -s /usr/share/zoneinfo/$zone /etc/localtime

Time sync – physiscal host only

see daemons/ntp

Ready to go

tune LILO or switch to whatever boot-loader you cherish.

Additional notes

skeletons

unless you’re running an FTP server across user account, you can keep those and also let non-login shell parms take place

# this works fine if you have /home/
#ln -s ../../etc/shrc /etc/skel/.bashrc

# this is safer if you have /home/ as a symlink
ln -s /etc/shrc /etc/skel/.bashrc

ksh93

Setup KSH93 / PDKSH to avoid Bash’s bind 'set disable-completion on/off dance, and enjoy happy-happy copy/pasting

git clone https://github.com/Orc/pdksh.git
cd pdksh/
./configure.sh
make
make install
echo /usr/local/bin/ksh >> /etc/shells

case "$-" in *i*)
    set -o emacs 2>/dev/null
    bind -m ^L='clear^M'
    bind ^I=complete-list

vi /etc/profile

ENV=/etc/shrc

vi /etc/shrc

keybd_trap () {
    case ${.sh.edchar} in
        $'\f')    .sh.edchar=$'\e\f';;  # clear-screen
        $'\e[1~') .sh.edchar=$'\001';;  # Home = beginning-of-line
        $'\e[4~') .sh.edchar=$'\005';;  # End = end-of-line
        $'\e[5~') .sh.edchar=$'\e>';;   # PgUp = history-previous
        $'\e[6~') .sh.edchar=$'\e<';;   # PgDn = history-next
        $'\e[3~') .sh.edchar=$'\004';;  # Delete = delete-char
    esac
}

case "$-" in *i*)
    set -o emacs 2>/dev/null

    #KSH93
    trap keybd_trap KEYBD

    #PDKSH
    bind -m ^L='clear^M'
    bind ^I=complete-list

chsh -s /bin/ksh root
useradd -D -s /bin/ksh

#chsh -s /usr/local/bin/ksh
#useradd -D -s /usr/local/bin/ksh

moar

Virtual Terminals (for physical host, as those do not exist in a slackware guest. I find it convenient to see what happened lately on the console, and if you really want to hide it, just ^L before you ^D.

cd /etc/
mv -i inittab inittab.dist
sed 's/agetty 38/agetty --noclear 38/' inittab.dist > inittab
diff -bu inittab.dist inittab

Clean local daemons' shutdown

cat > /etc/rc.d/rc.local_shutdown <<-EOF
#!/bin/bash

    PATH=$PATH:/usr/local/bin:/usr/local/sbin

EOF
chmod +x /etc/rc.d/rc.local_shutdown

The two rc.local scripts are executable by default

ln -s rc.d/rc.local /etc/rc.local
ln -s rc.d/rc.local_shutdown /etc/rc.local_shutdown
ls -lF /etc/rc.d/rc.local /etc/rc.d/rc.local_shutdown /etc/rc.local /etc/rc.local_shutdown

Eventually enable custom daily and weekly cron jobs

slackpkg install nmap libnl
nmap -V

cd /root/
wget https://pub.nethence.com/bin/system/DAILY.txt
mv DAILY.txt DAILY
chmod +x DAILY

wget https://pub.nethence.com/bin/system/WEEKLY.txt
mv WEEKLY.txt WEEKLY
chmod +x WEEKLY

vi /root/targets.conf

IP-ADDRESS
ANOTHER-CIDR

PATH cannot be defined in a dcron environment and its default is

/sbin:/usr/sbin:/bin:/usr/bin

therefore, in case your tools appear elsewhere, you need to provide the absolute full path accordingly

which sendmail

assuming your host is outbound email-ready

crontab -e

00 4 * * * /root/DAILY 2>&1
00 5 * * 0 /root/WEEKLY 2>&1

PATH can and should be defined within the cron-powered scripts, though

PATH=/usr/local/bin:/usr/local/sbin:/bin:/sbin:/usr/bin:/usr/sbin

Troubleshooting

getting this from your daily cron job

error: stat of /var/log/spooler failed: No such file or directory

==> got no spooler coz this is a minimalistic system

vi /etc/logrotate.d/syslog

(remove /var/log/spooler from the list)

you are also getting this once in a while

Stopping NTP daemon...
Starting NTP daemon:  /usr/sbin/ntpd -g -x -u ntp:ntp

==> and this is not particularly interesting so eventually get rid of it

vi /etc/logrotate.d/ntp

    [ -x /etc/rc.d/rc.ntpd ] && /etc/rc.d/rc.ntpd restart >/dev/null

when trying to SSH

PTY allocation request failed on channel 0

==> keep rc.udev

Trash

Loose the too-many shell features

#mkdir ~/.trash/
#mv /etc/profile.d/modules.* ~/.trash/

Some hardware checking

grep '^model name' /proc/cpuinfo | uniq
grep ^proc /proc/cpuinfo
free -m
hdparm -I /dev/sda | grep 'Sector size'
hdparm -Tt /dev/sda | tee -a /var/tmp/hdparm.sda
#hdparm -Tt /dev/xvda | tee -a /var/tmp/hdparm.xvda
#hdparm -Tt /dev/xvda1 | tee -a /var/tmp/hdparm.xvda1

One could further tune the cron job environment but that is unnecessary

SHELL=/bin/bash
PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin
MAILTO=root
HOME=/root

moar for /etc/profile

PKG_CONFIG_PATH=/usr/lib64/pkgconfig\
:/usr/local/lib/pkgconfig\
:/usr/local/lib64/pkgconfig\
:/usr/local/share/pkgconfig

Resources

slackware » beginners_guide https://docs.slackware.com/slackware:beginners_guide

Shells https://docs.slackware.com/howtos:cli_manual:shells

Difference between Login Shell and Non-Login Shell? https://unix.stackexchange.com/questions/38175/difference-between-login-shell-and-non-login-shell

Current directory abbreviation rule in shell prompt https://unix.stackexchange.com/questions/245107/current-directory-abbreviation-rule-in-shell-prompt

Colour colour everywhere! 256 colour-mode for Linux consoles http://www.robmeerman.co.uk/unix/256colours

Localization: Adapt Slackware to your own Language https://docs.slackware.com/slackware:localization

ntp

“ntpq -p” output http://nlug.ml1.co.uk/2012/01/ntpq-p-output/831

3.3. Clock Quality http://www.ntp.org/ntpfaq/NTP-s-sw-clocks-quality.htm

Xen domU VM time drifts out of sync with dom0 and other domU - IBM System x https://www.ibm.com/support/pages/xen-domu-vm-time-drifts-out-sync-dom0-and-other-domu-ibm-system-x

how do you set up a linux client to use ntp information provided through dhcp? https://unix.stackexchange.com/questions/327954/how-do-you-set-up-a-linux-client-to-use-ntp-information-provided-through-dhcp