Chapter 23: IPv6
STANDARD Revision 1.0
C4® CMTS Release 8.3 User Guide
© 2016 ARRIS Enterprises LLC. All Rights Reserved.
745
(2009:0DB8:85A2:0631::/64) from the DHCPv6 server. This causes a collision, since both SYS-1 and SYS-2 have the PD route
for this prefix.
This collision is detected by both C4/c CMTSs while processing the IGP packets because both C4/c CMTSs are redistributing
these PD routes into IGP. When the collision is detected, both C4/c CMTSs check to see if the modem is online. SYS-1 finds
that modem is offline and purges the PD route for this prefix. SYS-2 finds that modem is online and keeps the PD route in
its routing table.
This clears up the collision since SYS-1 removed the PD route from its routing table and IGP no longer has two updates
from two different C4/c CMTSs for the same route.
Verify that the PDs belonging to the residential customers in one C4/c CMTS are not visible in the other C4/c CMTS. The
second C4/c CMTS should have only one route, learned through IGP, representing all of the residential customers in the
first C4/c CMTS and vice versa. For example: SYS-2 will see only one route FC0D:C422:FFFF::/48 advertised by SYS-1.
Similarly, SYS-1 will see only one route FC0D:C420:FFFF::/48 advertised by SYS-2.
The PD 2009:0DB8:85A2:0631::/64 is for the commercial customer and is seen by both the C4/c CMTSs. In one C4/c CMTS
it is a PD route; in the other it is an IGP learned route.
Below are the outputs from the
show route
command for the IS-IS configuration discussed above after the modem has
been moved. These outputs, one for each C4/c CMTS, show that each of the C4/c CMTSs has four residential PDs delegated
in addition to the one commercial customer who moved from SYS-1 to SYS-2:
SYS-1 show ipv6 route include-pd
Codes: (L1) internal level-1, (L2) internal level-2, (eL1) external level-1,
(eL2) external level-2 (S) summary, (IA) inter-area,
(E1) external type-1, (E2) external type-2, (I) internal,
(E) external
ACT Active-IS, IS Inactive-IS, OOS Inactive-OOS
Dist/
IPv6 Route Dest / mask Act Next Hop Metric Protocol RouteAge Interface
================ === =============================== ====== ======= ======= =========
::/0
ACT 2001:cada:c422:1700::1 1/0 netmgmt 4 days gigE 17/2.0
2009:0db8:85a2:0631/64 ACT fe80::216:46ff:fe88:5bbf 18/20 isis(eL1) 00:01:10 gigE 17/2.0
fc0d:c420:ffff::/48 ACT fe80::216:46ff:fe88:5bbf 118/20 isis(eL1) 00:02:10 gigE 17/2.0
fc0d:c422:ffff::/48 ACT ::
1/0 netmgmt 4 days null 0
fc0d:c422:ffff:25::/64 ACT fe80::217:13ff:fe05:122 2/0 pd 01:46:46 cMac 1.0
fc0d:c422:ffff:26::/64 ACT fe80::217:13ff:fe05:108 2/0 pd 01:46:46 cMac 1.0
fc0d:c422:ffff:27::/64 ACT fe80::217:13ff:fe05:10d 2/0 pd 01:46:46 cMac 1.0
fc0d:c422:ffff:28::/64 ACT fe80::217:13ff:fe05:101 2/0 pd 01:46:46 cMac 1.0
2001:cada:c422:1702/64 ACT 2001:cada:c422:1702::2 0/0 local 02:18:46 gigE 17/2.0
SYS-2 show ipv6 route include-pd
Codes: (L1) internal level-1, (L2) internal level-2, (eL1) external level-1
(eL2) external level-2, (S) summary, (IA) inter-area
(E1) external type-1, (E2) external type-2, (I) internal
(E) external, (iIA) internal inter-area, (eIA) external inter-area
