Debianのネットワーク設定

ホスト名

ホスト名の確認

# cat /etc/hostname

ホスト名の変更

# vi /etc/hostname

ネットワーク情報

ネットワークデバイス名の確認

# ip a
1: 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
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host noprefixroute 
       valid_lft forever preferred_lft forever
2: eno1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
    link/ether ??:??:??:??:??:?? brd ff:ff:ff:ff:ff:ff
    altname enp2s0
    altname enx????????????
3: enp4s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether ??:??:??:??:??:?? brd ff:ff:ff:ff:ff:ff
    altname enx????????????
    inet 192.168.103.213/24 brd 192.168.103.255 scope global dynamic noprefixroute enp4s0
       valid_lft 85836sec preferred_lft 75036sec
    inet6 240d:1a:3ce:ba00:4943:9310:ce3f:d58d/64 scope global dynamic mngtmpaddr noprefixroute 
       valid_lft 86341sec preferred_lft 86341sec
    inet6 fe80::12b:5152:6c1e:fc50/64 scope link 
       valid_lft forever preferred_lft forever
4: wlp3s0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
    link/ether ??:??:??:??:??:?? brd ff:ff:ff:ff:ff:ff
    altname wlx????????????

ネットワークのハードウェア情報の確認

ネットワークデバイスが何のハードウェアかは、以下のコマンで確認できます(ログは一部抜粋したもの)

# lshw -C network
  *-network DISABLED
       description: Ethernet interface
       product: RTL8111/8168/8211/8411 PCI Express Gigabit Ethernet Controller
       vendor: Realtek Semiconductor Co., Ltd.
       logical name: eno1
  *-network DISABLED
       description: Wireless interface
       product: Wi-Fi 6 AX200
       vendor: Intel Corporation
       logical name: wlp3s0
  *-network
       description: Ethernet interface
       product: Ethernet Controller I226-V
       vendor: Intel Corporation
       logical name: enp4s0

固定IP設定

現在のネットワーク設定確認

inet dhcp なら DHCP、inet static なら固定IPです

# cat /etc/network/interfaces
# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

source /etc/network/interfaces.d/*

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
allow-hotplug enp4s0
iface enp4s0 inet dhcp

固定IP設定

各値は自分の環境に合わせ設定すること

# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

source /etc/network/interfaces.d/*

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
allow-hotplug enp4s0
iface enp4s0 inet static
    address         192.168.103.103
    netmask         255.255.255.0
    network         192.168.103.0
    broadcast       192.168.103.255
    gateway         192.168.103.1
    dns-nameservers 192.168.103.1

設定が終わったら、設定を反映

# systemctl restart ifup@enp4s0

SSH設定

設定ファイルのバックアップ

# cp /etc/ssh/sshd_config /etc/ssh/sshd_config.org

使用済みポートの確認

# ss -atnu
Netid       State        Recv-Q       Send-Q               Local Address:Port                Peer Address:Port       
tcp         LISTEN       0            128                        0.0.0.0:22                       0.0.0.0:*          
tcp         ESTAB        0            52                 192.168.103.103:22               192.168.103.126:61628      
tcp         LISTEN       0            128                           [::]:22                          [::]:*    

設定を検討する項目

ポート番号の変更デフォルトの22を使うXXXXXを使う
#Port 22Port XXXXX
パスワード認証許可禁止
#PasswordAuthentication yesPasswordAuthentication no
公開鍵認証禁止許可
#PubkeyAuthentication yesPubkeyAuthentication yes
 root ログイン許可禁止
PermitRootLogin yesPermitRootLogin no

鍵の作成

$ ssh-keygen 
Generating public/private ed25519 key pair.
Enter file in which to save the key (/home/hoge/.ssh/id_ed25519): 
Enter passphrase for "/home/hoge/.ssh/id_ed25519" (empty for no passphrase): 
Enter same passphrase again: 
Your identification has been saved in /home/hoge/.ssh/id_ed25519
Your public key has been saved in /home/hoge/.ssh/id_ed25519.pub
The key fingerprint is:
SHA256:mmhImSeMBGgMLZSzXxm0tO12/aaOgY38qwUWBENo6Ug hoge@ylocalhost
The key's randomart image is:
+--[ED25519 256]--+
|Bo. =*..         |
|+E.+..*          |
|oo*  ooo         |
|.= + o. . .      |
|. B o  =S. .     |
| . = .+o*   .    |
|  . o o+ +   o   |
|   .    o o o    |
|       ..+oo     |
+----[SHA256]-----+

プライベートキーを取り出したらサーバーからは削除
パブリックキーは authorized_keys にリネーム

$ rm .ssh/id_ed25519
$ mv .ssh/id_ed25519.pub .ssh/authorized_keys

コメント

タイトルとURLをコピーしました