Solution : https://service.sap.com/sap/support/notes/1366742 (SAP Service marketplace login required)
Key words : 
hostname lookup cache [semicolon separated, ignore list open http, dupplicated hostnames/ip addresses, special hostnames/ip addresses, cluster internal ip addresses, hostnames/ip addresses excluded, reverse lookup issue, <port>/accconfig/baseconfigurationservlet, hostname/ip address, managed services runs
Related Notes : 
       
| 1366774 | Monitoring Errors for Resources in ACC | 
| 1084753 | Issues with sapacosprep |