Linux connect: Network is unreachable

在虚拟机中ping，发现网络不通：

[root@node01 ~]# ping 114.114.114.114
connect: Network is unreachable

发生此问题时，环境如下： 

●网络连接选择的是NAT模式

●虚拟网络配置中NAT模式配置如下：

 ●/etc/sysconfig/network-scripts/ifcfg-ens33文件内容为

TYPE=Ethernet
PROXY_METHOD=none
BROWSER_ONLY=no
BOOTPROTO=static
DEFROUTE=yes
IPV4_FAILURE_FATAL=no
IPV6INIT=yes
IPV6_AUTOCONF=yes
IPV6_DEFROUTE=yes
IPV6_FAILURE_FATAL=no
IPV6_ADDR_GEN_MODE=stable-privacy
NAME=ens33
DEVICE=ens33
ONBOOT=yes
IPADDR=192.168.30.136
NETMASK=255.255.255.0
GETWAY=192.168.30.1
DNS1=114.114.114.114

●ip信息为

[root@node01 ~]# ifconfig
ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.30.136  netmask 255.255.255.0  broadcast 192.168.30.255
        inet6 fe80::20c:29ff:fe4c:9347  prefixlen 64  scopeid 0x20<link>
        inet6 fd15:4ba5:5a2b:1008:20c:29ff:fe4c:9347  prefixlen 64  scopeid 0x0<global>
        ether 00:0c:29:4c:93:47  txqueuelen 1000  (Ethernet)
        RX packets 628  bytes 61587 (60.1 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 505  bytes 75815 (74.0 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        loop  txqueuelen 1000  (Local Loopback)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 0  bytes 0 (0.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

　　

参考 “linux关于connect: network is unreachable 问题的解决”（https://blog.csdn.net/xueshao110/article/details/79263498 ）这篇博文，添加默认网关问题得到解决：

[root@node01 ~]# route add default gw 192.168.30.1
[root@node01 ~]# route
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
default         gateway         0.0.0.0         UG    0      0        0 ens33
link-local      0.0.0.0         255.255.0.0     U     1002   0        0 ens33
192.168.30.0    0.0.0.0         255.255.255.0   U     0      0        0 ens33

　　

[root@node01 ~]# ping 114.114.114.114
PING 114.114.114.114 (114.114.114.114) 56(84) bytes of data.
64 bytes from 114.114.114.114: icmp_seq=1 ttl=128 time=6.97 ms
64 bytes from 114.114.114.114: icmp_seq=2 ttl=128 time=6.72 ms
64 bytes from 114.114.114.114: icmp_seq=3 ttl=128 time=7.60 ms
64 bytes from 114.114.114.114: icmp_seq=4 ttl=128 time=4.84 ms
64 bytes from 114.114.114.114: icmp_seq=5 ttl=128 time=6.32 ms
^C
--- 114.114.114.114 ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 4008ms
rtt min/avg/max/mdev = 4.841/6.493/7.603/0.928 ms