[Tempest] SSH exception "No existing session"

[Rodolfo Alonso]

Seen in several CI jobs:
https://storage.gra.cloud.ovh.net/v1/AUTH_dcaab5e32b234d56b626f72581e3644c/zuul_opendev_logs_820/611605/22/gate/neutron-tempest-plugin-scenario-linuxbridge/82023b2/testr_results.html
https://storage.bhs.cloud.ovh.net/v1/AUTH_dcaab5e32b234d56b626f72581e3644c/zuul_opendev_logs_ca7/653883/11/check/neutron-tempest-plugin-scenario-linuxbridge/ca7d140/testr_results.html

Error [1]:
2020-01-21 00:35:15,421 31613 INFO [tempest.lib.common.ssh] Creating ssh connection to '172.24.5.164:22' as 'cirros' with public key authentication
2020-01-21 00:35:15,462 31613 INFO [paramiko.transport] Connected (version 2.0, client dropbear_2012.55)
2020-01-21 00:35:17,402 31613 INFO [paramiko.transport] Authentication (publickey) successful!
2020-01-21 00:35:17,402 31613 INFO [tempest.lib.common.ssh] ssh connection to cirros@172.24.5.164 successfully created
2020-01-21 00:35:17,855 31613 INFO [tempest.lib.common.ssh] Creating ssh connection to '172.24.5.164:22' as 'cirros' with public key authentication
2020-01-21 00:35:17,890 31613 INFO [paramiko.transport] Connected (version 2.0, client dropbear_2012.55)
2020-01-21 00:35:19,780 31613 INFO [paramiko.transport] Authentication (publickey) successful!
2020-01-21 00:35:19,780 31613 INFO [tempest.lib.common.ssh] ssh connection to cirros@172.24.5.164 successfully created
2020-01-21 00:35:19,856 31613 INFO [tempest.lib.common.ssh] Creating ssh connection to '172.24.5.164:22' as 'cirros' with public key authentication
2020-01-21 00:35:19,865 31613 INFO [paramiko.transport] Connected (version 2.0, client dropbear_2012.55)
2020-01-21 00:35:29,878 31613 ERROR [tempest.lib.common.ssh] Failed to establish authenticated ssh connection to cirros@172.24.5.164 after 0 attempts
2020-01-21 00:35:29.878 31613 ERROR tempest.lib.common.ssh Traceback (most recent call last):
2020-01-21 00:35:29.878 31613 ERROR tempest.lib.common.ssh File "/opt/stack/tempest/tempest/lib/common/ssh.py", line 107, in _get_ssh_connection
2020-01-21 00:35:29.878 31613 ERROR tempest.lib.common.ssh sock=proxy_chan)
2020-01-21 00:35:29.878 31613 ERROR tempest.lib.common.ssh File "/opt/stack/tempest/.tox/tempest/lib/python3.6/site-packages/paramiko/client.py", line 412, in connect
2020-01-21 00:35:29.878 31613 ERROR tempest.lib.common.ssh server_key = t.get_remote_server_key()
2020-01-21 00:35:29.878 31613 ERROR tempest.lib.common.ssh File "/opt/stack/tempest/.tox/tempest/lib/python3.6/site-packages/paramiko/transport.py", line 834, in get_remote_server_key
2020-01-21 00:35:29.878 31613 ERROR tempest.lib.common.ssh raise SSHException("No existing session")
2020-01-21 00:35:29.878 31613 ERROR tempest.lib.common.ssh paramiko.ssh_exception.SSHException: No existing session
2020-01-21 00:35:29.878 31613 ERROR tempest.lib.common.ssh

[1] http://paste.openstack.org/show/788688/

[Lajos Katona (lajos-katona)]

As I see from logstash this happens only with linuxbridge (if you delete the build_name query at least it shows only linuxbridge jobs):
http://logstash.openstack.org/#dashboard/file/logstash.json?query=message%3A%5C%22raise%20SSHException(%5C%5C%5C%22No%20existing%20session%5C%5C%5C%22)%5C%22%20AND%20build_name%3A%5C%22neutron-tempest-plugin-scenario-linuxbridge%5C%22

[Rodolfo Alonso (rodolfo-alonso-hernandez)]

Related patch: https://review.opendev.org/#/c/703852/