During the heat tempest tests the test_stack_list_respond test fails with a 500 error when making the list_stacks call. Looking at the heat api logs it shows a file not found error when trying to authenticate using keystoneclient. I'm assuming this somethign with devstack, but I didn't see any related cert errors in the devstack log.
The logs are located here:
http://logs.openstack.org/33705/1/gate/gate-tempest-devstack-vm-postgres-full/24558/logs/
but the relevant error in the heat log is:
2013-06-20 04:27:39.264 17571 DEBUG heat.api.middleware.version_negotiation [-] Processing request: GET /v1/82561ca957b04affaf526597aeda48a0/stacks Accept: process_request /opt/stack/new/heat/heat/api/middleware/version_negotiation.py:51
2013-06-20 04:27:39.265 17571 DEBUG heat.api.middleware.version_negotiation [-] Matched versioned URI. Version: 1.0 process_request /opt/stack/new/heat/heat/api/middleware/version_negotiation.py:66
2013-06-20 04:27:39.265 17571 DEBUG keystoneclient.middleware.auth_token [-] Authenticating user token __call__ /opt/stack/new/python-keystoneclient/keystoneclient/middleware/auth_token.py:449
2013-06-20 04:27:39.265 17571 DEBUG keystoneclient.middleware.auth_token [-] Removing headers from request environment: X-Identity-Status,X-Domain-Id,X-Domain-Name,X-Project-Id,X-Project-Name,X-Project-Domain-Id,X-Project-Domain-Name,X-User-Id,X-User-Name,X-User-Domain-Id,X-User-Domain-Name,X-Roles,X-Service-Catalog,X-User,X-Tenant-Id,X-Tenant-Name,X-Tenant,X-Role _remove_auth_headers /opt/stack/new/python-keystoneclient/keystoneclient/middleware/auth_token.py:507
2013-06-20 04:27:39.629 17571 ERROR keystoneclient.common.cms [-] Verify error: Error opening certificate file /var/cache/heat/api/signing_cert.pem
140668382041760:error:02001002:system library:fopen:No such file or directory:bss_file.c:169:fopen('/var/cache/heat/api/signing_cert.pem','r')
140668382041760:error:2006D080:BIO routines:BIO_new_file:no such file:bss_file.c:172:
2013-06-20 04:27:39.643 17571 ERROR keystoneclient.common.cms [-] Verify error: Error loading file /var/cache/heat/api/cacert.pem
139777343317664:error:02001002:system library:fopen:No such file or directory:bss_file.c:169:fopen('/var/cache/heat/api/cacert.pem','r')
139777343317664:error:2006D080:BIO routines:BIO_new_file:no such file:bss_file.c:172:
139777343317664:error:0B084002:x509 certificate routines:X509_load_cert_crl_file:system lib:by_file.c:274: