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Configuration > System Tools > DateTime : Understanding date and time management : Guidelines for setting system date and time
Guidelines for setting system date and time
Keeping the system date and time correct is important to ensure that the storage system can service requests correctly.
To automatically keep your storage system time synchronized, you need the name of at least one time server. For best results, supply the name of more than one time server if one becomes unavailable.
There are two protocols you can use for time synchronization: SNTP and rdate. SNTP (Simple Network Time Protocol) is more accurate; therefore, it is the preferred protocol.
If you cannot access an SNTP server, you can use rdate. Many UNIX servers can function as an rdate server; work with your system administrator to set up or identify an rdate server in your environment.