'(CentOS 7 Networking Tools)
Audience: sysadmins
“Networking is an essential part of building wealth.” — Armstrong Williams
The networking toolchain is a bit different on every OS. I’ve been spending enough time on CentOS 7 lately that its specifics are worth recording.
I’ll assume you don’t care about OSs that deviate much from RH-derived. I’m also leaving out anything to do with IPv6.
Wireless networking is not something you do much on servers, so it (iw) is
mostly omitted, too.
Packages
iproute2
Commands
The ip command has replaced some of the trusty old guard. If you use Zsh, the
ip tab-completion is excellent for quickly using various subcommands.
wolfram cidr
ethtool
ip a
ip link
ifconfig
ifstat
ifup/ifdown
nmcli/nmtui
nmcli d s
NetworkManager (need it for firewalld)
sys
netstat -tulpn netstat -pn tcp netstat -ln4 netstat -naf inet
ss (socket stat)
netcat
arp
route
iotop
iostat
iperf3
host
whois/dig
ping
lsof -ni
tcpdump
ipcalc
ifrename
sockstack -4
Although traceroute is the old standard, the netadmins I’ve worked with tend
to ask for mtr output.
mtr/tracepath
firewall-cmd
iostat -xdm 5
Files
/etc/sysconfig/network-scripts/ifcfg-e* /etc/services /etc/resolv.conf
Normal Things
pinging local Gb network: 0.15 ms
Antiquated/Deprecated
arp iptunnel iwconfig nameif netstat route ifconfig traceroute tcpdump
yum install net-tools (last release 2001 https://lists.debian.org/debian-devel/2009/03/msg00780.html)
Glossary
- uplink
-
incoming network drop
- layers (physical, datalink, network, transport, app)
- tcp/ip
- nat
- private addresses
-
10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16 https://en.wikipedia.org/wiki/Private_network
- arp/mac address
- cidr
- lan
- vlan (multi-homing)
- netmask
- broadcast
- gateway
- icmp
- mtu
- ttl
- snmp
-
simple network management protocol
- cat5e
-
the only cable you probably want to use
Resources
This could become a short ebook: DevOps Practical Guide to Modern Linux Networking