RHCSA Rapid Track
In this exercise, you will inspect the network configuration of one of your servers.
Outcomes
Identify the current network interfaces and basic network addresses.
Log in as the student user on workstation using student as the password.
From workstation, run the lab net-validate start command.
The command runs a start script that determine if the host, servera, is reachable on the network.
[student@workstation ~]$lab net-validate start
Use the ssh command to log in to
serveraas thestudentuser. The systems are configured to use SSH keys for authentication and passwordless access toservera.[student@workstation ~]$ssh student@servera...output omitted...[student@servera ~]$Important
Network interface names are determined by their bus type and the detection order of devices during boot. Your network interface names will vary according to the course platform and hardware in use.
On your system now, locate the interface name (such as
ens06oren1p2) associated with the Ethernet address52:54:00:00:fa:0a. Use this interface name to replace theenplaceholder used throughout this exercise.XLocate the network interface name associated with the Ethernet address
52:54:00:00:fa:0a. Record or remember this name and use it to replace theenplaceholder in subsequent commands.X[student@servera ~]$ip link1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 2:en: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000 link/etherX52:54:00:00:fa:0abrd ff:ff:ff:ff:ff:ffDisplay the current IP address and netmask for all interfaces.
[student@servera ~]$ip addr1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00inet 127.0.0.1/8scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2:en: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000 link/ether 52:54:00:00:fa:0a brd ff:ff:ff:ff:ff:ffXinet 172.25.250.10/24brd 172.25.250.255 scope global noprefixroute ens3 valid_lft forever preferred_lft forever inet6 fe80::3059:5462:198:58b2/64 scope link noprefixroute valid_lft forever preferred_lft foreverDisplay the statistics for the
eninterface.X[student@servera ~]$ip -s link show en2:Xen: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP mode DEFAULT group default qlen 1000 link/ether 52:54:00:00:fa:0a brd ff:ff:ff:ff:ff:ff RX: bytes packets errors dropped overrun mcast 89014225 168251 0 154418 0 0 TX: bytes packets errors dropped carrier collsns 608808 6090 0 0 0 0XDisplay the routing information.
[student@servera ~]$ip routedefault via 172.25.250.254 dev enXproto static metric 100 172.25.250.0/24 dev enXproto kernel scope link src 172.25.250.10 metric 100Verify that the router is accessible.
[student@servera ~]$ping -c3 172.25.250.254PING 172.25.250.254 (172.25.250.254) 56(84) bytes of data. 64 bytes from 172.25.250.254: icmp_seq=1 ttl=64 time=0.196 ms 64 bytes from 172.25.250.254: icmp_seq=2 ttl=64 time=0.436 ms 64 bytes from 172.25.250.254: icmp_seq=3 ttl=64 time=0.361 ms --- 172.25.250.254 ping statistics --- 3 packets transmitted, 3 received, 0% packet loss, time 49ms rtt min/avg/max/mdev = 0.196/0.331/0.436/0.100 msShow all the hops between the local system and
classroom.example.com.[student@servera ~]$tracepath classroom.example.com1?: [LOCALHOST] pmtu 1500 1: workstation.lab.example.com 0.270ms 1: workstation.lab.example.com 0.167ms 2: classroom.example.com 0.473ms reached Resume: pmtu 1500 hops 2 back 2Display the listening TCP sockets on the local system.
[student@servera ~]$ss -ltState Recv-Q Send-Q Local Address:Port Peer Address:Port LISTEN 0 128 0.0.0.0:sunrpc 0.0.0.0:* LISTEN 0 128 0.0.0.0:ssh 0.0.0.0:* LISTEN 0 128 [::]:sunrpc [::]:* LISTEN 0 128 [::]:ssh [::]:*Exit from
servera.[student@servera ~]$exitlogout Connection to servera closed. [student@workstation ~]$