The Dynamic ICL
feature allows you to configure ICL on the 1 GigE satellite ports 42 and 43
apart from the designated four 10GigE ports on the Cisco ASR 9000v and Cisco
ASR 9000v2 satellites. The Cisco ASR 9000v satellites can have, by default, up
to 6 potential ICLs. These are the four 10 GigE ports(44-47) and two 1 GigE
ports (42-43) and 42 fixed 1 GigE access ports (0-41). The two 1 GigE ports
(42-43) that are considered as potential ICLs are special ports that can be
used either as ICLs or as access ports. When these two ports (42-43) are
configured as access ports, they are not considered as potential ICLs
thereafter and therefore behave like any other 1 GigE access ports till the
next reload. When the satellite reloads and comes back up, those two ports
again become as potential ICLs. When the satellite gets discovered and connects
back to the host and if the host cross-link configuration still has the ports
42 and 43 as access ports, then these ports again switch to the access port
mode and exhibit the behavior like any other 1 GigE access ports. This feature
is supported on all the existing satellite topologies.
In case of dual head
satellite network topology, if any of these ports (42-43) is configured as
access port in at least one of the host and if that host becomes active, then
that port are not considered as potential ICLs anymore till next satellite
reload. Also, the two ports (42 and 43) when used as access ports, lose the
link integrity when the satellite reloads. The remote devices connected to
these two ports stay up momentarily just after the satellite reload and till
the satellite gets connected to the host and receives the cross-link
configuration again.
You cannot bundle
Dynamic ICL ports that are of dissimilar types. For example, you cannot bundle
1GigE and 10GigE ports.
Dynamic ICL is supported on
10G ports on Cisco NCS 5000 Series satellite either as an access port or an ICL
fabric port based on user configurations done through the configurable fabric
port functionality. By default, the highest 2x10G ports on both Cisco NCS 5001
(38 and 39) and Cisco NCS 5002 (78 and 79) are turned on as the ICL ports in
the satellite mode (only the highest 10G port turns on for plug and play in
factory reset / default mode). When the links come up over these default fabric
ports and the satellite is connected, you can configure a list of candidate
fabric ports. This gives the flexibility of using ports other than the default
fabric ports as additional ICLs.
The default fabric ports
(highest 2x10G ports) and the configured fabric ports lose link-integrity even
if they are later configured as access ports until the satellite discovery goes
down next. The default fabric ports permanently lose link integrity as they
come up as potential ICLs every time the cross-link mapping to an ICL goes
away. This is a necessary trade off to have certain ports available for zero
touch plug and play. Therefore, at instances where link integrity is crucial,
the default fabric ports, either must not be connected to such peers or must be
connected over non-revertive switch-over topologies.
Configurable fabric ports
All satellite hardware
variants have default set of fabric ports (permanent as well as dynamic) that
can be used to connect them as ICLs. These include 4x10G ports and the highest
2x1G ports (port 42,43) for Cisco ASR 9000v. For Cisco NCS 5000 series
satellites, these include 4x100G ports and the highest 2x10G ports. The highest
1G/10G ports are dynamic ICLs that can either be used as access ports or as
ICLs based on whether they have an active mapping to another ICL at a given
time or not.
Apart from these ports, the
host also allows additional 10G ports on Cisco NCS 5000 series satellites to be
configured as fabric ports. These are configurable as Candidate Fabric Ports on
the host under the nV satellite global configuration. When the configured list
is accepted, the satellite reports these interfaces to the host (including the
default/permanent candidate fabric ports) and subsequently sends change
notifications when that set changes or during re-synchronization with the host.
The satellite might choose to reject some of these configured candidate fabric
ports if they are already being used as active access ports. As in the case of
the normal Satellite nV System fabric ports, these interfaces are deleted if
they have no configuration presence and become inactive in the fabric topology,
either as notified by the satellite over the topology channel, or if the
satellite is entirely undiscovered by the host. The information about the nV
fabric port, and specifically fabric port statistics, does not persist across
deletion and re-creation of an nV Fabric interface with the same name.
An overlapping configuration
using the same port as both access port and candidate fabric port is not
recommended. However, when such a configuration is used, the behavior depends
on the chronological ordering of whether the port was first discovered as an
ICL or whether it got mapped as an access port to another active ICL. While a
configuration is rejected to map the port in one mode when the port is already
active in the other mode, there might be cases where the candidate fabric port
is configured and is waiting to be discovered. If it is also mapped as an
access port to another ICL, then the port becomes an active access port and
cannot be discovered thereafter, until the access port mapping goes away.
The list of permanent and
configured fabric ports, including their acceptance status is displayed in the
status of show commands under
Monitoring the
Satellite Software section.
Note |
With respect to the
existing dynamic ICLs, link integrity is not supported for ports configured as
fabric ports. Therefore, if they are also used as access ports, the ports will
come up as soon as the access port mapping goes away. This is required for
listening to discovery when they act as dynamic fabric ports.
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Note |
In the case of
Cisco IOS XR Software Release 6.0.1, this feature is only supported on Cisco
NCS 5000 series satellites.
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