Ip Address Reuse - Avaya one-X 1603SW Administrator's Manual

Other Network Considerations

IP Address Reuse

The SIP software has processing functionality to reuse IP Addresses during the DHCP process.
IP Address reuse prevents infinite looping when separate VLAN servers are used for voice and
data VLANs, and response is received from the DHCP server on the data VLAN, but not on the
voice VLAN.
Unless otherwise indicated, the values described here during IP address reuse are internally
provisioned or set by the process itself and not by manual administration.
Router(s) in Use:
if no responses are received from the router(s) indicated in the configuration parameter
ROUTER (set using DHCP Option 3 or by a local administrative procedure), and if REUSE = 1,
then ROUTER_IN_USE will be set to REUSE_ROUTER_IN_USE. With the exception of the
ROUTER configuration parameter, the other router-related parameters are internally set system
values.
VLAN Check:
During the VLAN check, if a reset is to be done and VLAN_IN_USE is not zero, VLAN_IN_USE
will be added to VLANLIST if it is not already on VLANLIST.
The VLAN detection process described in VLAN Detection on page 84 is followed If tagging is
off or if tagging is on and L2QVLAN is > 0, and if REUSETIME > 0, and if REUSE_IPADD is not
"0.0.0.0". If VLANTEST expires, the value of VLAN_IN_USE is added to VLANLIST if it is not
already on VLANLIST.
If a DHCPOFFER is not received within REUSETIME seconds, or if a DHCPOFFER is received
that contains a value of L2QVLAN that is on VLANLIST, REUSE will be set to 1, IPADD will be
set to the value of REUSE_IPADD, NETMASK will be set to the value of REUSE_NETMASK,
ROUTER will be set to the value of REUSE_ROUTERS, and if the value of REUSE_TAGGING
is 1, 802.1Q tagging will be turned on with a VLAN ID equal to the value of L2QVLAN_INIT,
DHCP will then enter the "extended" REBINDING state, and operation will proceed as normal.
After a successful registration, the following system values are set:
REUSE_IPADD will be set to the value of IPADD,
REUSE_NETMASK will be set to the value of NETMASK,
REUSE_ROUTERS will be set to the value of ROUTER,
REUSE_ROUTER_IN_USE will be set to the value of ROUTER_IN_USE,
REUSE_TAGGING will be set to the value of TAGGING,
L2QVLAN_INIT will be set to the value of VLAN_IN_USE,
the MIB object endptVLANLIST will be set to the value of VLANLIST and then the value of
VLANLIST will be set to null.
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