Error fix. Magento system.log shows Warning:Redis::connect()

Our [login to view URL] keeps recording the same warning: 2019-02-18T19:47:09+00:00 ERR (3): Warning: Redis::connect(): php_network_getaddresses: getaddrinfo failed: Name or service not known in /srv/users/serverpilot/apps/.../public/.modman/Cm_RedisSession/app/code/local/Credis/[login to view URL] on line 456 We installed Cm_RedisSession for our magento 1.9 ([login to view URL]) We have a dedicated Redis server connected with private ip. I have pinged it through our main server with no issue, cannot locate the problem. Tried to set pm.max_requests = 500 pm.process_idle_timeout=10s but it does not fix the issue, neither. May related to server configuration.