Cisco Cisco IOS Software Releases 12.2 MC

The Cisco MWR 1900 router does not support online insertion and removal (OIR) of WAN interface 
cards. Any attempt to perform OIR on a card in a powered up router might cause damage to the card.

Removing the compact flash from the Cisco MWR 1900 router during a read/write operation might 
corrupt the contents of the compact flash, rendering it useless. To recover from an accidental removal of 
or corruption to the compact flash, a maintenance spare with the appropriate bootable Cisco IOS 
software image might be needed.

The Cisco MWR 1900 router requires a special version of Cisco IOS software. Not all Cisco IOS 
software features can be used with the Cisco MWR 1900 router as the core routing is handled by the 
network processor. The following standard Cisco IOS software features are not supported on the Cisco 
MWR 1900 router:

Security Access Control Lists

MPLS

802.1Q VLANs

Frame Relay (FR)

MLP LFI

ATM

When upgrading the image on your Cisco MWR 1900 router, power cycle the router or perform a 
microcode reload on the VWIC-2MFT-T1-DIR to ensure that the firmware for the VWIC-2MFT-T1-DIR 
is updated during the upgrade.

To fully disable PPP multiplexing (PPPMux), issue the no ppp mux command on the T1 interfaces of 
the routers at both ends of the T1 link. If PPP multiplexing remains configured on one side of the link, 
that side will offer to receive PPP multiplexed packets.

MLP LFI is not supported by the Cisco MWR 1900 router. Therefore, MLP LFI must be disabled on peer 
devices connecting to the Cisco MWR 1900 router T1 MLP connections.