The restricted output to SSH stuff:

Jan 21 01:25:31 stress-test-23357 cloud-init[990]: [CLOUDINIT] stages.py[DEBUG]: Running module ssh (<module 'cloudinit.config.cc_ssh' from '/usr/lib/python3/dist-packages/cloudinit/config/cc_ssh.py'>) with frequency once-per-instance
Jan 21 01:25:31 stress-test-23357 cloud-init[990]: [CLOUDINIT] handlers.py[DEBUG]: start: init-network/config-ssh: running config-ssh with frequency once-per-instance
Jan 21 01:25:31 stress-test-23357 cloud-init[990]: [CLOUDINIT] util.py[DEBUG]: Writing to /var/lib/cloud/instances/a94ea439-445e-447c-9227-64f71802ff61/sem/config_ssh - wb: [420] 24 bytes
Jan 21 01:25:31 stress-test-23357 cloud-init[990]: [CLOUDINIT] helpers.py[DEBUG]: Running config-ssh using lock (<FileLock using file '/var/lib/cloud/instances/a94ea439-445e-447c-9227-64f71802ff61/sem/config_ssh'>)
Jan 21 01:25:31 stress-test-23357 cloud-init[990]: [CLOUDINIT] util.py[DEBUG]: Running command ['ssh-keygen', '-t', 'rsa', '-N', '', '-f', '/etc/ssh/ssh_host_rsa_key'] with allowed return codes [0] (shell=False, capture=True)
Jan 21 01:25:31 stress-test-23357 cloud-init[990]: [CLOUDINIT] util.py[DEBUG]: Running command ['ssh-keygen', '-t', 'dsa', '-N', '', '-f', '/etc/ssh/ssh_host_dsa_key'] with allowed return codes [0] (shell=False, capture=True)
Jan 21 01:25:31 stress-test-23357 cloud-init[990]: [CLOUDINIT] util.py[DEBUG]: Running command ['ssh-keygen', '-t', 'ecdsa', '-N', '', '-f', '/etc/ssh/ssh_host_ecdsa_key'] with allowed return codes [0] (shell=False,capture=True)
Jan 21 01:25:31 stress-test-23357 cloud-init[990]: [CLOUDINIT] util.py[DEBUG]: Running command ['ssh-keygen', '-t', 'ed25519', '-N', '', '-f', '/etc/ssh/ssh_host_ed25519_key'] with allowed return codes [0] (shell=False, capture=True)
Jan 21 01:25:31 stress-test-23357 cloud-init[990]: [CLOUDINIT] util.py[DEBUG]: Changing the ownership of /home/ubuntu/.ssh to 1000:1000
Jan 21 01:25:31 stress-test-23357 cloud-init[990]: [CLOUDINIT] util.py[DEBUG]: Reading from /etc/ssh/sshd_config (quiet=False)
Jan 21 01:25:31 stress-test-23357 cloud-init[990]: [CLOUDINIT] util.py[DEBUG]: Read 2531 bytes from /etc/ssh/sshd_config
Jan 21 01:25:31 stress-test-23357 cloud-init[990]: [CLOUDINIT] util.py[DEBUG]: Writing to /home/ubuntu/.ssh/authorized_keys - wb: [384] 213 bytes
Jan 21 01:25:31 stress-test-23357 cloud-init[990]: [CLOUDINIT] util.py[DEBUG]: Changing the ownership of /home/ubuntu/.ssh/authorized_keys to 1000:1000
Jan 21 01:25:31 stress-test-23357 cloud-init[990]: [CLOUDINIT] util.py[DEBUG]: Changing the ownership of /root/.ssh to 0:0
Jan 21 01:25:31 stress-test-23357 cloud-init[990]: [CLOUDINIT] util.py[DEBUG]: Reading from /etc/ssh/sshd_config (quiet=False)
Jan 21 01:25:31 stress-test-23357 cloud-init[990]: [CLOUDINIT] util.py[DEBUG]: Read 2531 bytes from /etc/ssh/sshd_config
Jan 21 01:25:31 stress-test-23357 cloud-init[990]: [CLOUDINIT] util.py[DEBUG]: Writing to /root/.ssh/authorized_keys - wb: [384] 213 bytes
Jan 21 01:25:31 stress-test-23357 cloud-init[990]: [CLOUDINIT] util.py[DEBUG]: Changing the ownership of /root/.ssh/authorized_keys to 0:0
Jan 21 01:25:31 stress-test-23357 cloud-init[990]: [CLOUDINIT] handlers.py[DEBUG]: finish: init-network/config-ssh: SUCCESS: config-ssh ran successfully
Jan 21 01:25:31 stress-test-23357 cloud-init[990]: Your identification has been saved in /etc/ssh/ssh_host_rsa_key.
Jan 21 01:25:31 stress-test-23357 cloud-init[990]: Your public key has been saved in /etc/ssh/ssh_host_rsa_key.pub.
Jan 21 01:25:32 stress-test-23357 cloud-init[990]: Your identification has been saved in /etc/ssh/ssh_host_dsa_key.
Jan 21 01:25:32 stress-test-23357 cloud-init[990]: Your public key has been saved in /etc/ssh/ssh_host_dsa_key.pub.
Jan 21 01:25:32 stress-test-23357 cloud-init[990]: Your identification has been saved in /etc/ssh/ssh_host_ecdsa_key.
Jan 21 01:25:32 stress-test-23357 cloud-init[990]: Your public key has been saved in /etc/ssh/ssh_host_ecdsa_key.pub.
Jan 21 01:25:32 stress-test-23357 cloud-init[990]: Your identification has been saved in /etc/ssh/ssh_host_ed25519_key.
Jan 21 01:25:32 stress-test-23357 cloud-init[990]: Your public key has been saved in /etc/ssh/ssh_host_ed25519_key.pub.
Jan 21 01:25:32 stress-test-23357 cloud-init[1115]: [CLOUDINIT] stages.py[DEBUG]: Running module ssh-import-id (<module 'cloudinit.config.cc_ssh_import_id' from '/usr/lib/python3/dist-packages/cloudinit/config/cc_ssh_import_id.py'>) with frequency once-per-instance
Jan 21 01:25:32 stress-test-23357 cloud-init[1115]: [CLOUDINIT] handlers.py[DEBUG]: start: modules-config/config-ssh-import-id: running config-ssh-import-id with frequency once-per-instance
Jan 21 01:25:32 stress-test-23357 cloud-init[1115]: [CLOUDINIT] util.py[DEBUG]: Writing to /var/lib/cloud/instances/a94ea439-445e-447c-9227-64f71802ff61/sem/config_ssh_import_id - wb: [420] 25 bytes
Jan 21 01:25:32 stress-test-23357 cloud-init[1115]: [CLOUDINIT] helpers.py[DEBUG]: Running config-ssh-import-id using lock (<FileLock using file '/var/lib/cloud/instances/a94ea439-445e-447c-9227-64f71802ff61/sem/config_ssh_import_id'>)
Jan 21 01:25:32 stress-test-23357 cloud-init[1115]: [CLOUDINIT] handlers.py[DEBUG]: finish: modules-config/config-ssh-import-id: SUCCESS: config-ssh-import-id ran successfully
Jan 21 01:25:33 stress-test-23357 sshd[1303]: Server listening on 0.0.0.0 port 22.
Jan 21 01:25:33 stress-test-23357 sshd[1303]: Server listening on :: port 22.
Jan 21 01:25:33 stress-test-23357 cloud-init[1115]: [CLOUDINIT] util.py[DEBUG]: Reading from /etc/ssh/sshd_config (quiet=False)
Jan 21 01:25:33 stress-test-23357 cloud-init[1115]: [CLOUDINIT] util.py[DEBUG]: Read 2531 bytes from /etc/ssh/sshd_config
Jan 21 01:25:33 stress-test-23357 cloud-init[1115]: [CLOUDINIT] util.py[DEBUG]: Writing to /etc/ssh/sshd_config - wb: [420] 2527 bytes
Jan 21 01:25:33 stress-test-23357 sshd[1303]: Received signal 15; terminating.
Jan 21 01:25:33 stress-test-23357 sshd[1316]: Did not receive identification string from 85.0.154.127
Jan 21 01:25:33 stress-test-23357 sshd[1317]: Server listening on 0.0.0.0 port 22.
Jan 21 01:25:33 stress-test-23357 sshd[1317]: Server listening on :: port 22.
Jan 21 01:25:33 stress-test-23357 cloud-init[1115]: [CLOUDINIT] cc_set_passwords.py[DEBUG]: Restarted the ssh daemon

We can see the client that has been rejected due to restart.