Use Friendly DNS Names (Hostnames) instead of IP Addresses in TOP Server

Important Notes:

• If your DNS server/servers have delays in updating their records when your device IP address changes, those delays can affect TOP Server’s ability to reconnect quickly on a device IP address change. This can result in bad quality data and “Device Not Responding” errors while TOP Server waits for the new IP to appear in the DNS settings.
• If you are still using TOP Server V5.7 or older, the Admin level settings Cache Lifetime and Request Pool are used to manually define how long a host name is cached before checking the DNS server and how many simultaneous requests can be made at a time to the DNS server.
  • These settings in V5.7 or older are found under the TOP Server Admin settings in the Host Resolution section.
  • Cache Lifetime - If you know your IP addresses will not change at a high frequency, set the Cache Lifetime to a higher value than the default but to a time that is shorter than the change interval of your IP address. If you are using devices with dynamic IP addresses, it is common for the provider of your dynamic IP addresses to have assigned a “Default Lease Time” for your IP addresses. Ask them what that is and set TOP Server’s Cache Lifetime setting to less than their Default Lease Time. If you do not know how often your IP addresses change, leave this setting at the default to insure maximum responsiveness. Cache lifetime can be set as high as 7200 seconds.
  • Request Pool - This setting is useful if you have a large number of channels and IP addresses that change frequently. TOP Server can perform up to 8 simultaneous DNS lookups/requests to help maintain performance. TOP Server will queue requests once the Maximum outstanding requests number is reached. Most DNS lookups are very quick, so for most users the default is sufficient. Increase the Maximum outstanding requests setting if you have a large number of devices and their IP addresses that change very frequently, or if your DNS servers are slow to respond.