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Cisco 1921 Gigabit router

Background

Replaces Cisco ADSL & 1841 router as this is a Fast Ethernet only router, the 1921 is a similar router but with Ge0/0 and Ge0/1 interfaces and two hwic slots. I have a EHWIC-1GE-SFP-CU card as well because in the foreseeable future I may need to bring the internet in from the ISP ONT some distance away, so a utp to fibre next to the ONT would link to the WIC SFP port.

Also, there is a USB port in addition to the serial connector, this implements a usb to serial converter internally, it shows up as /dev/ttyACM0.

Note this is NOT the direct fibre from the ISP, they provide a single WDM / TDM fibre to the Optical Network Terminator (ONT) as part of the G-PON WAN network, then a Ethernet copper RJ45 from the ONT to a fibre converter and on to the 1941 SFP fibre in a different building.

First problem...

Router#sh diag
Slot 0:
        WIC Slot 0:
        Unknown WAN daughter card
        WIC module not supported/disabled in this slot
        PCB Serial Number        : FOC15164VRP
        Hardware Revision        : 1.0
   ... edited ...    
        Product (FRU) Number     : EHWIC-1GE-SFP-CU

I'm running

Cisco IOS Software, C1900 Software (C1900-UNIVERSALK9-M), Version 15.0(1)M4, RELEASE SOFTWARE (fc1)

And the Cisco Support page for the EHWIC says the 1921 requires Cisco 1921 ISR - Release 15.1(4)M

So I need to find this IOS release first.

Carrying on without the WIC interface, just a copy and paste from the previous but with GigabitEthernet rather than FastEthernet.

I had this problem before enabling SSH but didn't document it:-

Please create RSA keys to enable SSH (and of atleast 768 bits for SSH v2).

Solution is to create the key. Many helpful posts on the various forums etc. BUT none seemed to specify the commands below needed to be run in the conf t session not just at the command line.

router01(config)#crypto key generate rsa modulus 2048
The name for the keys will be: router01.rainsbrook.co.uk

% The key modulus size is 2048 bits
% Generating 2048 bit RSA keys, keys will be non-exportable...[OK]

int-router01(config)#
*Jun 20 15:24:41.599: %SSH-5-ENABLED: SSH 2.0 has been enabled
router01(config)#

Banner text for a multiline statement is a bit unusual:-

router01(config)#banner login $      
Enter TEXT message.  End with the character '$'
+-------------------------------------------------------+
|                                                       |
|  Legal Warning - Access forbidden unless authorized   |
|                                                       |
+-------------------------------------------------------+

$
router01(config)#

Updating Flash

Having found an appropriate IOS which supports my WIC, I was ablr to tftp the file up to the flash: on the router, and then set the boot image to use the new image.

If two images are present in flash, the router will boot off the first image it finds, this may not be the one you require, so set a boot image line. Once this is deemed stable, I will probably remove it from the router to an archive, and there will not be a requirement to set the image.

router01#
router01# copy tftp: flash:                    
Address or name of remote host ? 
Source filename ? 
Destination filename [c1900-universalk9-mz.SPA.157-3.M2.bin]? 
Accessing tftp://192.168.x.y/c1900-universalk9-mz.SPA.157-3.M2.bin...
Loading c1900-universalk9-mz.SPA.157-3.M2.bin from 192.168.x.y (via GigabitEthernet0/1): !!!!!!!!!!!!!!!!
[OK - 85245200 bytes]

85245200 bytes copied in 99.340 secs (858116 bytes/sec)

router01#
router01#sh flash: 
-#- --length-- -----date/time------ path
1     45801276 Jul 26 2012 09:32:54 c1900-universalk9-mz.SPA.150-1.M4.bin
2     85245200 Nov 16 2025 22:15:32 c1900-universalk9-mz.SPA.157-3.M2.bin

125562880 bytes available (131047424 bytes used)
router01#

router01#conf t
Enter configuration commands, one per line.  End with CNTL/Z.

router01(config)#boot system flash c1900-universalk9-mz.SPA.157-3.M2.bin
router01(config)#exit
router01# copy run sta
router01#

Network Side

Bit off topic but may be of some interest.

Optical Network Terminator

Just for completeness, this is the ONT. It has a single fibre input from OpenReach and a Gigabit ethernet port on an RJ45 for the Subs side interface. The optical technology used for this is GPON.

https://www.draytek.co.uk/information/blog/gpon-fibre-fttp-what-is-it-and-how-does-it-work

https://www.cisco.com/c/en/us/support/docs/switches/catalyst-pon-series/216230-understand-gpon-technology.html

OpenReach ONT