gfw allow all icap_send_client_ip on icap_send_client_username on icap_client_username_header X-Authenticated-User icap_retry allow all icap_retry_limit -1
gfw allow all icap_send_client_ip on icap_send_client_username on icap_client_username_header X-Authenticated-User icap_retry allow all icap_retry_limit -1 ICAPのサポートを有効に
gfw allow all icap_send_client_ip on icap_send_client_username on icap_client_username_header X-Authenticated-User icap_retry allow all icap_retry_limit -1 ICAPサーバを指定 ID どのタイミングでICAPサーバに渡すか (request or response)
gfw allow all icap_send_client_ip on icap_send_client_username on icap_client_username_header X-Authenticated-User icap_retry allow all icap_retry_limit -1 ICAPサーバにユーザのIPを渡す