Problem
The webclient shows “HTTP/1.1 503 Service Unavailable”, and the /opt/zimbra/log/mailbox.log file has the following error:
2016-06-02 10:15:33,436 INFO [qtp509886383-1033602:http://127.0.0.1:80/service/soap/AuthRequest] [] misc - Access to IP 10.10.10.3suspended, for repeated failed login. 2016-06-02 10:15:33,437 WARN [qtp509886383-1033601:https://63.237.45.232:443/zimbra/] [] webclient - system failure: error while proxying request to target server: HTTP/1.1 503 Service Unavailable com.zimbra.common.service.ServiceException: system failure: error while proxying request to target server: HTTP/1.1 503 Service Unavailable
Solution
White-list the IP addresses:
su - zimbra zmprov mcf +zimbraHttpThrottleSafeIPs 10.1.2.3/32 zmprov mcf +zimbraHttpThrottleSafeIPs 192.168.4.0/24
If whitelisting isn’t possible, disable the DoS filter for the repeated login failure:
su - zimbra zmprov mcf zimbraInvalidLoginFilterMaxFailedLogin 0
Then restart the mailbox services to reflect the changes:
zmmailboxdctl restart
Submitted by: Sourabh Bhushan
