Manage Networking in RHEL - RHCSA (RH124).pdf

Manage Networking in RHEL - RHCSA (RH124).pdf

• 1.
  Manage Linux Networking
• 2.
  Static IP vsDynamic IP Feature Static IP Dynamic IP Configuratio n Manually set in device's network settings or by network administrator Automatically assigned by DHCP (Dynamic Host Configuration Protocol) server Stability Remains constant, providing consistent access to network resources Can change periodically or with each network connection Network Monitoring Easier to monitor and track devices due to predictable addresses May require more sophisticated monitoring systems to track changing addresses Suitable for Servers, networked devices requiring constant and predictable access. Home network & networks with frequent changes in devices/ configurations
• 3.
  ● Network Interface:Hardware/software component that connects a device to a network. ● MAC Address: Unique identifier assigned to a network interface by its manufacturer. ● Subnet Mask: Divides an IP address into network and host parts. ● Gateway: Entry and exit point for a network, enabling communication between devices on different networks. ● DNS (Domain Name System): Translates human-readable domain names into IP addresses. OS Network Components
• 4.
  Two ways toget ip address: 1. Command: ifconfig
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  2. Command: ipaddr
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  Check system gatewayinformation ● Command: netstat-rnv To get the information about the domain and DNS server address ● Command: nslookup <site-name>
• 7.
  Verify 'NetworkManager' servicestatus ● Command: systemctl status NetworkManager Manage network interfaces with nmcli
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  CLI based toolto inspect available network interfaces ● Command: nmcli
• 9.
  Modify a networkinterface to set a static IPv4 address ● Command: nmcli connection modify <interface_name> ipv4.addresses <static_ip_address> Set the gateway address for a network interface ● Command: nmcli connection modify <interface_name> ipv4.gateway <gateway_ip_address> Ip and gateway configuration
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  Change IP assignmentmethod to manual ● Command: nmcli connection modify <interface_name> ipv4.method <method> DNS Configuration Set the DNS server ● Command: nmcli connection modify <interface_name> ipv4.dns <dns_address>
• 11.
  Restart the networkinterface ● Command: nmcli connection down <interface_name> && nmcli connection up <interface_name> Add secondary ipv4 address to the interface ● Command: nmcli connection modify <interface_name> +ipv4.addresses <secondary_ipv4_address> Note: Restart and confirm the changes
• 12.
  Network Configuration Usingnmtui 1. Text-based interface for managing and configuring network settings Command: nmtui
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  3. Choose theinterface to edit its configuration 4. Add the ip address while navigating to the IP Address configuration
• 14.
  Access the networkconfiguration scripts ● Command: cd <path_to_network_scripts_directory> Network files
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  Review the contentsof the 'hosts' file ● Command: cat <path_to_hosts_file> Note: The file stores the system's hostname, and changes will take effect after a reboot
• 16.
  Modify the DNSserver address in the system's resolver configuration file ● Command: sudo vi /etc/resolv.conf
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  View the systemconfiguration file that specifies the order and sources for system database lookups ● Command: sudo cat <path_to_configuration_file>
• 18.
  Basic Commands ● ping-primaryTCP/IP command used to troubleshoot connectivity, reachability ● traceroute- Trace the route taken by the packets to reach the target device ● tcpdump-Captures and analyzes network traffic passing through a specific interface ● ethtool-To get ethernet adapter details of a network interface ● dig-Get the information about domain names, commonly used for troubleshooting DNS issues