When trying to retrieve update sets and testing the connection under 'update sources' from prod and to dev, failing with error "authentication to the remote instance failed".

From the localhost logs : 

2019-01-15 08:16:18 (454) Default-thread-15 C736DBC54F0B2700E714FAF01210C7D4 txid=873b5b054f4b OUTBOUND_HTTP: protocol=HTTP/1.1 response_status=200 response_time=596 request_length=0 response_length=-2 app_scope=global session_id=C736DBC54F0B2700E714FAF01210C7D4 transaction_name="#507237 /xmlhttp.do" user_name=<user>@<domain> mid_server= source_table= source_record= system_id=<node-name>.service-now.com:<port> method=GET log_level=Basic scheme=https hostname=<instance-name>.service-now.com path=/hub.do url=https://<instance-name>.service-now.com/hub.do

2019-01-15 08:16:18 (455) Default-thread-15 C736DBC54F0B2700E714FAF01210C7D4 txid=873b5b054f4b WARNING *** WARNING *** OUTBOUND USAGE ANALYTICS - OutboundUsageAnalytics : OutboundUsageAnalytics: Usage analytics send failed 
2019-01-15 08:16:18 (593) Default-thread-15 C736DBC54F0B2700E714FAF01210C7D4 txid=873b5b054f4b *** End #507237 /xmlhttp.do, user: <user>@<domain>, total time: 0:00:00.754, processing time: 0:00:00.754, SQL time: 0:00:00.001 (count: 5)

• User records used for authentication in sys_update_set_source [ Update Source ] record were storing partial or truncated LDAP information in the 'source' field.
• Source Instances are configured to use SSO for authentication through the UI (browser).

However, SSO cannot be used when making web service calls between instances (which is how update sets are moved). 

1. Remove 'source' field values from the user record
2. Save

OR

1. Navigate to LDAP > Properties
2. Find property "Use LDAP for password authentication"
3. Uncheck the "Use LDAP for password authentication" checkbox
   • The instance falls back to local authentication and will use the password stored in the User record [sys_user.user_password].