VPRN Service Configuration Commands
Page 994 7750 SR OS Services Guide
config>service>vprn>sub-if>grp-if>dhcp
Description According to RFC 3046, DHCP Relay Agent Information Option, a DHCP request where the giaddr is 
0.0.0.0 and which contains a Option 82 field in the packet, should be discarded, unless it arrives on a 
"trusted" circuit. If trusted mode is enabled on an IP interface, the relay agent (the SR-Series) will 
modify the request's giaddr to be equal to the ingress interface and forward the request. 
Note that this behavior only applies when the action in the Relay Agent Information Option is "keep". 
In the case where the Option 82 field is being replaced by the relay agent (action = "replace"), the 
original Option 82 information is lost anyway, and there is thus no reason for enabling the trusted 
option.
The no form of this command returns the system to the default.
Default not enabled
host-connectivity-verify
Syntax host-connectivity-verify [interval interval] [action {remove|alarm}]
Context config>service>vprn>if>sap
config>service>vprn>sub-if>grp-if
config>service>vprn>sub-if>grp-if>dhcp
Description This command enables enables subscriber host connectivity verification on a given SAP within a 
service. This tool will periodically scan all known hosts (from dhcp-state) and perform a UC ARP 
request. The subscriber host connectivity verification will maintain state (connected vs. not-
connected) for all hosts.
Default no host-connectivity-verify
Parameters interval interval — The interval, expressed in minutes, which specifies the time interval which all 
known sources should be verified. The actual rate is then dependent on number of known hosts 
and interval. 
Values 1— 6000
Note that a zero value can be used by the SNMP agent to disable host-connectivity-
verify.
action {remove | alarm} — Defines the action taken on a subscriber host connectivity verification 
failure for a given host. The remove keyword raises an alarm and removes dhcp-state and 
releases all allocated resources (queues, table entries, etc.). DHCP-RELEASE will be signaled to 
corresponding DHCP server. Static hosts will never be removed. The alarm keyword raises an 
alarm indicating that the host is disconnected.