[LINUX] Connect to centos6 on virtualbox with ssh connection from Mac

environment

Guest OS: CentOS6 Host OS: MacOS Catalina

flow

① Open the network with virtualbox settings

・ Set below. Allocation: Host-only adapter ・ Confirmation of name Name: vboxnet0

② Start centos

③ Check the network on centos

Check the network with ʻip a` on centos. In the case of my setting, I confirmed that eth2 was added by the setting of ①, but the IP address was not set in eth2. It is unknown why it was eth2 instead of eth1. ..

> ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN 
------abridgement---------
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    inet 10.0.2.15/24 brd 10.0.2.255 scope global eth0
    inet6 fe80::a00:27ff:fe84:eb71/64 scope link 
3: eth2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
↑ No IP address listed

④ Set the IP address in eth2.

Set manually. (1) Add the configuration file for eth2 under / etc / sysconfig / network-scripts /. I have / etc / sysconfig / network-scripts / ifcfg-eth0 but not / etc / sysconfig / network-scripts / ifcfg-eth2, so I copied the ifcfg-eth0 file.

> cd /etc/sysconfig/network-scripts/
> ls
ifcfg-eth0      ifdown-ippp    ifup-aliases    ifup-ppp
ifdown-ipv6     ifup-bnep      ifup-routes     ifdown-isdn
ifup-eth        ifup-sit       ifdown-post     ifup-ippp
ifup-tunnel     ifdown-ppp     ifup-ipv6       ifup-wireless
ifcfg-lo        ifdown-routes  ifup-isdn       init.ipv6-global
ifdown          ifdown-sit     ifup-plip       net.hotplug
ifdown-bnep     ifdown-tunnel  ifup-plusb      network-functions
ifdown-eth      ifup           ifup-post       network-functions-ipv6
↑　ifcfg-There is no eth2 file.

> cp ifcfg-eth0 ifcfg-eth2

⑵ Check the network status of mac. Check the network address of the name (vboxnet0) set in the virtualbox network with ifconfig from the terminal. Derived from the IP address and subnet mask. If the IP address is 192.168.56.1/24, 192.168.56.0 will be the network address.

(3) Change the ifcfg-eth2 file that you copied earlier to the correct contents. As it is, it is exactly the same as the ifcfg-eth0 file!

Change before

DEVICE=eth0
HWADDR=＊＊＊＊＊＊＊＊＊＊＊＊
TYPE=Ethernet
UUID=＊＊＊＊＊＊＊＊＊＊＊＊
ONBOOT=yes
NM_CONTROLLED=yes
BOOTPROTO=dhcp

↓ Change to the following

After change

DEVICE=eth2
# HWADDR=＊＊＊＊＊＊＊＊＊＊＊＊ Comment out
TYPE=Ethernet
# UUID=＊＊＊＊＊＊＊＊＊＊＊＊ Comment out
ONBOOT=yes
NM_CONTROLLED=ye
BOOTPROTO=none ← changed from dhcp
IPADDR=192.168.56.2 ← added
PREFIX=24 ← added

・ DEVICE is specified as eth2 (Here, eth2 was newly added in ʻip a earlier, so match it) If eth1 etc. is output by ʻip a, enter the output device name -Change BOOTPROTO from dhcp to none so that the IP address is not automatically assigned. -Add an address that can be assigned to the network address confirmed in (2) to IPADDR. Since I was using 192.168.56.1 on my mac, I set it to 192.168.56.2. PREFIX is set to the same value as confirmed in ⑵.

⑤ Restart the network and complete the connection from the terminal!

centos6

service network restart

Terminal

ssh [email protected]

About this setting

・ About host-only adapter I increased the NIC by adding a host-only adapter in virualbox. The host-only adapter is set to connect only the host OS (MacOS) and guest OS (CentOS6), and cannot be connected to the outside. ・ This connection method The NIC on the host OS side (192.168.56.1 in this example) and the NIC on the guest OS side (192.168.56.2 in this example) were connected.