RHCSA Rapid Track

Reset your serverX system.

1. Display the current IP address and netmask for all interfaces.

   [student@serverX ~]$ ip addr
   1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN 
       link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
       inet 127.0.0.1/8 scope host lo
          valid_lft forever preferred_lft forever
       inet6 ::1/128 scope host 
          valid_lft forever preferred_lft forever
   2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
       link/ether 52:54:00:00:00:0b brd ff:ff:ff:ff:ff:ff
       inet 172.25.X.11/24 brd 172.25.X.255 scope global dynamic eth0
          valid_lft 12704sec preferred_lft 12704sec
       inet6 fe80::5054:ff:fe00:b/64 scope link 
          valid_lft forever preferred_lft forever
   

2. Display the statistics for the eth0 interface.

   [student@serverX ~]$ ip -s link show eth0
   2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT qlen 1000
       link/ether 52:54:00:00:00:0b brd ff:ff:ff:ff:ff:ff
       RX: bytes  packets  errors  dropped overrun mcast   
       418398     4588     0       0       0       0      
       TX: bytes  packets  errors  dropped carrier collsns 
       360733     1730     0       0       0       0      
   

3. Display the routing information.

   [student@serverX ~]$ ip route
   default via 172.25.X.254 dev eth0  proto static  metric 1024 
   172.25.X.0/24 dev eth0  proto kernel  scope link  src 172.25.X.11 
   

4. Verify that the router is accessible.

   [student@serverX ~]$ ping -c3 172.25.X.254
   PING 172.25.X.254 (172.25.X.254) 56(84) bytes of data.
   64 bytes from 172.25.X.254: icmp_seq=1 ttl=64 time=0.489 ms
   64 bytes from 172.25.X.254: icmp_seq=2 ttl=64 time=0.510 ms
   64 bytes from 172.25.X.254: icmp_seq=3 ttl=64 time=0.458 ms
   
   --- 172.25.X.254 ping statistics ---
   3 packets transmitted, 3 received, 0% packet loss, time 1999ms
   rtt min/avg/max/mdev = 0.458/0.485/0.510/0.033 ms
   

5. Show all the hops between the local system and classroom.example.com.

   [student@serverX ~]$ tracepath classroom.example.com
    1:  classroom.example.com                                 0.522ms !H
        Resume: pmtu 65535 
   

6. Display the listening TCP sockets on the local system.

   [student@serverX ~]$ ss -lt
   State      Recv-Q Send-Q      Local Address:Port          Peer Address:Port   
   LISTEN     0      128                     *:55630                    *:*       
   LISTEN     0      128                     *:sunrpc                   *:*       
   LISTEN     0      128                     *:ssh                      *:*       
   LISTEN     0      100             127.0.0.1:smtp                     *:*       
   LISTEN     0      128                    :::sunrpc                  :::*       
   LISTEN     0      128                    :::ssh                     :::*       
   LISTEN     0      128                    :::33079                   :::*       
   LISTEN     0      100                   ::1:smtp                    :::*