kazulog@sv1:~$ cat /etc/os-release | head -2
PRETTY_NAME="Ubuntu 26.04 LTS"
NAME="Ubuntu"
kazulog@sv1:~$ sshd -V
OpenSSH_10.2p1 Ubuntu-2ubuntu3.5, OpenSSL 3.5.5 27 Jan 2026
kazulog@sv1:~$ dpkg -l openssh-server | tail -1
ii  openssh-server 1:10.2p1-2ubuntu3.5 amd64        secure shell (SSH) server, for secure access from remote machines
kazulog@sv1:~$ systemctl status ssh --no-pager -l | cat
● ssh.service - OpenBSD Secure Shell server
     Loaded: loaded (/usr/lib/systemd/system/ssh.service; disabled; preset: enabled)
     Active: active (running) since Thu 2026-09-10 14:39:29 JST; 1min 39s ago
 Invocation: 049398a869f542468581164f8dd0f5af
TriggeredBy: ● ssh.socket
       Docs: man:sshd(8)
             man:sshd_config(5)
    Process: 1021 ExecStartPre=/usr/sbin/sshd -t (code=exited, status=0/SUCCESS)
   Main PID: 1060 (sshd)
      Tasks: 1 (limit: 1486)
     Memory: 7.7M (peak: 9.4M)
        CPU: 408ms
     CGroup: /system.slice/ssh.service
             └─1060 "sshd: /usr/sbin/sshd -D [listener] 0 of 10-100 startups"

Sep 10 14:40:00 sv1 sshd-session[1231]: Accepted publickey for kazulog from 10.100.3.1 port 63509 ssh2: ED25519 SHA256:NdURwOz/PbiL79UHvTtYE5vuTJfA2RD5RXsn/rG76rw
Sep 10 14:40:00 sv1 sshd-session[1231]: pam_unix(sshd:session): session opened for user kazulog(uid=1000) by kazulog(uid=0)
Sep 10 14:40:02 sv1 sshd-session[1367]: Accepted publickey for kazulog from 10.100.3.1 port 63510 ssh2: ED25519 SHA256:NdURwOz/PbiL79UHvTtYE5vuTJfA2RD5RXsn/rG76rw
Sep 10 14:40:02 sv1 sshd-session[1367]: pam_unix(sshd:session): session opened for user kazulog(uid=1000) by kazulog(uid=0)
Sep 10 14:40:03 sv1 sshd-session[1367]: syslogin_perform_logout: logout() returned an error
Sep 10 14:40:03 sv1 sshd-session[1367]: pam_unix(sshd:session): session closed for user kazulog
Sep 10 14:40:38 sv1 sshd-session[1584]: Accepted publickey for kazulog from 10.100.3.1 port 63530 ssh2: ED25519 SHA256:NdURwOz/PbiL79UHvTtYE5vuTJfA2RD5RXsn/rG76rw
Sep 10 14:40:38 sv1 sshd-session[1584]: pam_unix(sshd:session): session opened for user kazulog(uid=1000) by kazulog(uid=0)
Sep 10 14:41:07 sv1 sshd-session[1824]: Accepted publickey for kazulog from 10.100.3.1 port 63549 ssh2: ED25519 SHA256:NdURwOz/PbiL79UHvTtYE5vuTJfA2RD5RXsn/rG76rw
Sep 10 14:41:07 sv1 sshd-session[1824]: pam_unix(sshd:session): session opened for user kazulog(uid=1000) by kazulog(uid=0)
kazulog@sv1:~$ systemctl is-enabled ssh ssh.socket
disabled
enabled
kazulog@sv1:~$ ss -tlnp
State  Recv-Q Send-Q Local Address:Port Peer Address:PortProcess
LISTEN 0      4096      127.0.0.54:53        0.0.0.0:*          
LISTEN 0      4096   127.0.0.53%lo:53        0.0.0.0:*          
LISTEN 0      4096         0.0.0.0:22        0.0.0.0:*          
LISTEN 0      4096            [::]:22           [::]:*          
kazulog@sv1:~$ grep -n 'Include' /etc/ssh/sshd_config
24:Include /etc/ssh/sshd_config.d/*.conf
kazulog@sv1:~$ ls -l /etc/ssh/sshd_config.d/
total 8
-rw------- 1 root root 27 Sep 10 13:30 50-cloud-init.conf
-rw-r--r-- 1 root root 26 Aug 24 01:26 60-cloudimg-settings.conf
kazulog@sv1:~$ sudo head -100 /etc/ssh/sshd_config.d/50-cloud-init.conf /etc/ssh/sshd_config.d/60-cloudimg-settings.conf
==> /etc/ssh/sshd_config.d/50-cloud-init.conf <==
PasswordAuthentication yes

==> /etc/ssh/sshd_config.d/60-cloudimg-settings.conf <==
PasswordAuthentication no
kazulog@sv1:~$ sudo sshd -T | grep -iE '^(port|passwordauthentication|permitrootlogin|pubkeyauthentication|authorizedkeysfile)'
port 22
permitrootlogin prohibit-password
pubkeyauthentication yes
passwordauthentication yes
authorizedkeysfile .ssh/authorized_keys .ssh/authorized_keys2
kazulog@sv1:~$ ls -la ~/.ssh
total 12
drwx------ 2 kazulog kazulog 4096 Sep 10 13:30 .
drwxr-x--- 4 kazulog kazulog 4096 Sep 10 13:31 ..
-rw------- 1 kazulog kazulog  110 Sep 10 13:30 authorized_keys