User:Tom/RHCE EX300

RHCSA & RHCE Red Hat Enterprise Linux 7: Training and Exam Preparation Guide (EX200 and EX300) third edition march 205 by Asghar Ghori

RHCE

Hoofdstuk 14 Writing Shell Scripts

nl       Number lines of files
bash -x  Debug script

Command line arguments $0 $1, $#, $*, $$.
shift    Move arguments

echo -e  Enables interprestation of backslash escapes

$?       Exit code

test     Test conditions (man test) int1 -eq int2
if condition then action else action fi
if condition then action elif condition then action else action fi

for-do done
while do done
until do done

Hoofdstuk 15 Configuring Bonding, Teaming, IPv6 and Routing

modprobe bonding
modinfo bonding
uuidgen eth2

systemctl status NetworkManager
nmcli dev status
nmcli con add type bond con-name bond0 ifname bond0 mode balance-rr ip4 192.168.122.112 gw4 192.168.122.1
nmcli con add type bond-slave ifname eth1 master bond0
nmcli con up bond0
nmcli con show 

yum install teamd
modprobe team 
modinfo team
nmcli con add type team con-name team0 ifname team0 ip4 192.168.122.122/24 gw4 192.168.122.1
nmcli con add type team-slave con-name eth4 ifname eth4 master team0

IPv6 128bit 1204:bab1:21d1:bb43:23a1:9bde:87df:bac9
Zowel IPv4 als IPv6 adressen kunnen op een adapter gezet worden.
ping6

RIP    Routing Information protocol
OSPF   Open Shortest Path First
ip route, route, netstat -rn
ip route add
ip route del

Hoofdstuk 16 Synchronzing Time with NTP

ntpd used UDP over well-known port 123

NTP roles: Primary NTP server, Secondary NTP server, NTP peer, NTP client.

NTP Client can be configured as a polling, broadcast, multicast or manycast client.

Packages ntp and ntpdate
Commands ntpdate, ntpq, ntpd and ntpstat.

NTP Configuration file /etc/ntp.conf.
Key directives driftfile, logfile restrict, server, peer, broadcast, crypto, includefile, keys. See man ntp.conf.

Package system-config-date for system-config-date tool
Output ntpq -p is important

Hoofdstuk 17 Working with Firewalld and kerberos

firewall-cmd      --state, --get-default-zone, --get-active-zones, --get-zones, --list-all, --list-all-zones 
                  --list-all -zone public, 
                  --net-zone testzone --permanent, --delete-zone testzone --permanent
                  --get-services
                  --list-services
                  --query-service

/etc/firewalld/
/etc/firewalld/zones/             System-defined

/usr/lib/firewalld/zones/         User-defined