networking Materials
### Install DHCP Server [root@testos ~]# yum -y install dhcp ### Configure DHCP Server [root@testos ~]# vi /etc/dhcp/dhcpd.conf # create new # specify domain name option domain-name “unixtest.com”; # specify name server’s hostname or IP address option domain-name-servers testos.unixtest.com; # default lease time default-lease-time 600; # max lease time max-lease-time 7200; # this DHCP server … Read more
An aggregation is similar to an IPMP link created for failover, but has other advantages: Early versions of Solaris 10 do not have this facility – you would need to download the Sun Trunking software to get it. ### Solaris 10 configuration: To show the available network interfaces: [root @ soltest]~ # dladm show-link LINK … Read more
The dlstat and flowstat commands are tools for monitoring and obtaining statistics on network traffic on datalinks and flows, respectively. These commands parallel the dladm and flowadm commands. The following table shows the parallelism between the pair of *adm commands and the pair of *stat commands and their respective functions: Command Function dladm command options User interface and tool for configuring and administering datalinks. flowadm command options User interface … Read more
### Install Chrony. [root@testos ~]# yum -y install chrony ### Edit/Update Chrony Configuration file [root@testos ~]# vi /etc/chrony.conf ### line 3: change servers for synchronization #server 0.centos.pool.ntp.org iburst #server 1.centos.pool.ntp.org iburst #server 2.centos.pool.ntp.org iburst #server 3.centos.pool.ntp.org iburst server <NTP1 SERVER ADDRESS> iburst server <NTP2 SERVER ADDRESS> iburst server <NTP3 SERVER ADDRESS> iburst ### line 25: … Read more
### Install NTPd. [root@testos ~]# yum -y install ntp ### Edit/Update NTP Configuration file [root@testos ~]# vi /etc/ntp.conf ### line 18: add the network range you allow to receive requests restrict 10.0.0.0 mask 255.255.255.0 nomodify notrap ### change servers for synchronization ### change servers for synchronization #server 0.centos.pool.ntp.org iburst #server 1.centos.pool.ntp.org iburst #server 2.centos.pool.ntp.org iburst … Read more
//Check current ip configuration status # dladm show-phys # ipadm show-if # ipadm show-addr //Check the interfaces name # dladm show-phys — output Example —LINK MEDIA STATE SPEED DUPLEX DEVICEnet0 Ethernet up 1000 full e1000g0 –> Attentiom to this linenet1 Ethernet unknown 0 unknown pcn0 =============================================================================================== # ipadm create-ip net0 //Check status # ipadm show-if … Read more
Issue: Is it safe to disable Consistent Device Naming by setting net.ifnames=0 on the kernel command line in RHEL7, RHEL8 and RHEL9? Why can I no longer use the 70-persistent-net.rules file to force persistent ethX names like I could in earlier versions of Red Hat Enterprise Linux? Resolution: No. Red Hat strongly recommend that the … Read more
Use the following procedure if you need to preserve the IP configuration that is associated with one network device and then move that configuration to another network device. You might perform this procedure as a prelude to removing a network card from the system or when changing a network cable connection. For example purposes only, … Read more
Nmap is Linux command-line tool for network exploration and security auditing. This tool is generally used by hackers and cybersecurity enthusiasts and even by network and system administrators. It is used for the following purposes: Real time information of a network. This Nmap cheat sheet help you master what is arguably the most useful tool in … Read more
Virtual network computing (VNC) is a type of remote-control software that makes it possible to control another computer over a network connection. Keystrokes and mouse clicks are transmitted from one computer to another. ### Install VNC Server [root@testos ~]# yum install -y tigervnc-server ### If firewalld is running, allow VNC service [root@testos ~]# firewall-cmd –add-service=vnc-server … Read more