W&T 58031, Manual

Page: 26 / 217

26
W&T
Assigning the IP address
2.4.3 Lease-Time
The lease time determined and transmitted by the DHCP server
specifies the Time-To-Live of the assigned IP address. After half
the lease time has expired, the Com-Server attempts to extend
the time for the assigned DHCP server and up update the
address. If this is not possible by the time the lease time
expires, for example because the DHCP server can no longer
be reached, the Com-Server deletes the IP address and starts a
new cyclical search for alternate DHCP servers for the purpose
of assigning a new IP address.
Because of the absent clock, the lease time associated with the
current IP address is no longer available after a reset. After the
restart therefore a corresponding update request is issued with
the original DHCP server. If the latter is not resolvable at this
point in time, the Com-Server deletes the IP address and starts
a new cyclical search for alternate DHCP servers.
If DHCP is activated, the remaining lease time together with the
current IP address is displayed in the menu item
SETUP System
r
Setup TCP/IP
r
IP-Address using the format hh:mm:ss.
1
If after the assigned lease time has expired the DHCP
server is not reachable, the Com-Server deletes its IP
address. All existing TCP/UDP connections between the Com-
Server and other network clients are thereby closed. To prevent
such events, we recommend configuring the assigned lease
time in the DHCP server to infinite if possible.