We got two Solaris server which intermittently any of workstations couldn't connect (ping) the server. if I leave continues ping for couple minutes ping and then for another couple minutes doesn’t ping. If I do any network activity such as clear mac address cache (arp –d) or renew the IP Address (ipconfig /renew) it starts to ping and then stops and starts!
If I change the IP address of workstations then it works without any problem for a while and may back.
I should add just the problem with Solaris server and not with any other servers or internet.