UNIX for Advanced & Expert Users

PING 
root@server1:/home/server1# ifconfig
eth0      Link encap:Ethernet  HWaddr 00:23:ae:27:b9:ec  
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)
          Interrupt:16 

lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          RX packets:41 errors:0 dropped:0 overruns:0 frame:0
          TX packets:41 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:3589 (3.5 KiB)  TX bytes:3589 (3.5 KiB)

wlan0     Link encap:Ethernet  HWaddr 00:24:2c:49:d1:d8  
          inet addr:192.168.1.6  Bcast:192.168.1.255  Mask:255.255.255.0
          inet6 addr: fe80::224:2cff:fe49:d1d8/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:54 errors:0 dropped:0 overruns:0 frame:6492
          TX packets:100 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:5617 (5.4 KiB)  TX bytes:12808 (12.5 KiB)
          Interrupt:17 Base address:0xc000 

root@server1:/home/server1# ping6 localhost
PING localhost(localhost.wmcomputersystems) 56 data bytes
ping: sendmsg: Network is unreachable

::1             localhost

root@server1:/home/server1# cat /etc/hosts
#127.0.0.1	localhost
#::ffff:7f00:1	localhost.wmcomputersystems	::1
::1             localhost.wmcomputersystems     localhost
#127.0.1.1	server1
2620:7:a000::1  server1.wmcomputersystems.com	server1

# The following lines are desirable for IPv6 capable hosts
::1     localhost ip6-localhost ip6-loopback
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters

 ::1

root@server1:/home/server1# ip link
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default 
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eth0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN mode DEFAULT group default qlen 1000
    link/ether 00:23:ae:27:b9:ec brd ff:ff:ff:ff:ff:ff
3: wlan0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DORMANT group default qlen 1000
    link/ether 00:24:2c:49:d1:d8 brd ff:ff:ff:ff:ff:ff
root@server1:/home/server1# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         192.168.1.1     0.0.0.0         UG    1024   0        0 wlan0
169.254.0.0     0.0.0.0         255.255.0.0     U     1000   0        0 wlan0
192.168.1.0     0.0.0.0         255.255.255.0   U     0      0        0 wlan0

sysctl net.ipv6.conf.{all,default,lo}.disable_ipv6