"ifconfig" - Trace Routes to Remote Host

This section provides a tutorial example on how to use 'ifconfig' command to view and manage network interface configurations.

"ifconfig" is a command line tool that allows you to manage network interface configurations. Here are some examples on using the "ifconfig" command:

Display the current configuration of all network interfaces on my macOS computer:

herong$ ifconfig

eno1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
    inet 192.168.1.3  netmask 255.255.255.0  broadcast 192.168.1.255
    inet6 fe80::544a:****:****:****  prefixlen 64  scopeid 0x20<link>
    ether **:**:**:**:**:**  txqueuelen 1000  (Ethernet)
    RX packets 358283201  bytes 404511320097 (376.7 GiB)
    RX errors 0  dropped 9353582  overruns 0  frame 0
    TX packets 387050825  bytes 490915453990 (457.2 GiB)
    TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
    device interrupt 20  memory 0xf7c00000-f7c20000

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
    inet 127.0.0.1  netmask 255.0.0.0
    inet6 ::1  prefixlen 128  scopeid 0x10<host>
    loop  txqueuelen 1000  (Local Loopback)
    RX packets 72185509  bytes 358471493733 (333.8 GiB)
    RX errors 0  dropped 0  overruns 0  frame 0
    TX packets 72185509  bytes 358471493733 (333.8 GiB)
    TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

virbr0: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
    inet 192.168.122.1  netmask 255.255.255.0  broadcast 192.168.122.255
    ether 52:54:00:49:e8:8d  txqueuelen 1000  (Ethernet)
    RX packets 0  bytes 0 (0.0 B)
    RX errors 0  dropped 0  overruns 0  frame 0
    TX packets 0  bytes 0 (0.0 B)
    TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

What I can see from the output:

You can also add custom bridge interfaces and remove them:

# adding a bridge between en1 and en2
sudo ifconfig bridge1 create
sudo ifconfig bridge1 addm en1 addm en2

# removing the bridge
sudo ifconfig bridge1 deletem en1 deletem en2
sudo ifconfig bridge1 down
sudo ifconfig bridge1 destroy

Table of Contents

 About This Book

 Introduction to Linux Systems

 Cockpit - Web Portal for Administrator

 Process Management

 Files and Directories

 Users and Groups

 File Systems

 Block Devices and Partitions

 LVM (Logical Volume Manager)

 Installing CentOS

 SELinux - Security-Enhanced Linux

Network Connection on CentOS

 Setup Ethernet Connection on CentOS

 Network Firewall Tools on CentOS

 "firewalld" and "firewall-cmd" on CentOS

 Manage Multiple Firewall Zones

 "nftables" and "nft" on CentOS

 "iptables" Command on CentOS

 "nmap" - Network Mapper on CentOS

 Monitor Network Services on CentOS

"ifconfig" - Trace Routes to Remote Host

 "traceroute" - Trace Routes to Remote Host

 "route" - Upate Routing Table

 "netstat" - Display Network Statistics

 "lsof" - List of Open Files

 Software Package Manager on CentOS - DNF and YUM

 vsftpd - Very Secure FTP Daemon

 Postfix - Mail Transport Agent (MTA)

 Dovecot - IMAP and POP3 Server

 Email Client Tools - Mail User Agents (MUA)

 LDAP (Lightweight Directory Access Protocol)

 Administrative Tasks

 References

 Full Version in PDF/EPUB