Cisco ASR 903 Release Notes

2
Cisco IOS XE 3S Release Notes for the Cisco ASR 903 Router
OL-26630-08
Chapter
Limitations and Restrictions
Limitations and Restrictions in Cisco IOS XE Release 3.7(3)S
There are no changes in limitations and restrictions in Cisco IOS XE Release 3.7(3)S; the restrictions
from IOS XE Release 3.7(2)S still apply.
Limitations and Restrictions in Cisco IOS XE Release 3.7(2)S
The following limitations and restrictions apply to Cisco IOS XE Release 3.7(2)S for the
CiscoASR903Router:
• LFA FRR Limitations—Release 3.7.2 has the following limitations for Loop Free Alternate
Fast-reroute (LFA FRR):
– To enable LFA FRR, you must include the mpls ldp explicit-null command. The implicit-null
command is not supported.
– LFA FRR is not supported with equal cost multipath (ECMP).
– The ASR 903 supports up to 4000 LFA FRR routes.
– Remote LFA tunnels are not HA aware; hence they are SSO co-existent but not SSO compliant.
• The restrictions from IOS XE Release 3.7(0)S apply to Release 3.7(2). For more information, see
Limitations and Restrictions in Cisco IOS XE Release 3.7(0)S, page 2.
Limitations and Restrictions in Cisco IOS XE Release 3.7(1)aS
There are no changes in limitations and restrictions in Cisco IOS XE Release 3.7(1)aS; the restrictions
from IOS XE Release 3.7(0)S still apply.
Limitations and Restrictions in Cisco IOS XE Release 3.7(0)S
The following limitations apply to the Cisco ASR 903 Router in IOS XE Release 3.7(0)S:
ATM IMA Limitation
• You can create a maximum of 16 IMA groups on each T1/E1 interface module.
Bridge Domain Interface Limitation
• The mtu command is not supported on BDI interfaces; however the ip mtu command is supported.
Clocking and Timing Limitation
• Only a single clocking input source can be configured within each group of eight ports (0-7 and
8-15) on the T1/E1 interface module using the network-clock input-source command.
• Synchronous Ethernet clock sources are not supported with PTP. Conversely, PTP clock sources are
not supported with synchronous Ethernet. However, you can use hybrid clocking to allow the router
to obtain frequency using Synchronous Ethernet and phase using PTP.
EFP Limitation
• QinQ is not supported on trunk EFP interfaces.

Cisco ASR 903 Specifications

General

Brand	Cisco
Model	ASR 903
Category	Network Router
Language	English