Cisco – Why is the Cisco 877 Router booting with garbage characters throughout

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My Cisco 877 is booting with the following results, and I'm looking to understand why. The below is happening consistently. I'm doing this via console cable to my PC using HyperTerminal.

The first portion of the boot output is as expected. I reach: Self decompressing the image : #...# [OK]. From this point, junk characters are scattered throughout the boot output. I then reach Press RETURN to get started!

Here it gets stuck, slowly printing more garbage.

I assume this means the IOS image file is corrupt, considering the problems only occur immediately after decompressing the image. Is this accurate?

Is there a chance there is a hardware issue at fault here?

Would you expect this problem to be resolved by replacing the IOS image?

Most online resources I found on corrupt IOS images were in regard to being forced into ROMMON mode, or instructions on how to replace the image. I'm more interested in understanding the cause of the problem.

Best Answer

This looks like a serial speed issue. The first words you see are from the bootloader, which look fine, and then the IOS is set to another speed, hence the garbage.

Try to set up the terminal speed differently, like 9600/8N1, 38400/8N1,...

This will change the behavior as the output from the bootloader will be crippled, but once IOS is started, it should look nicer :)

Related Solutions

Cisco 877 – How to Use as a VPN Server

So according to Cisco's website, yes you can have your 877 be a server. But I would highly recommend against it. I setup a VPN solution with the 871 routers connecting to a head end 2800 router and had all kinds of problems. Lower end devices just are not made to handle a lot of simultaneous VPN connections. My recommendation would be to buy a 2800 or 3800 series router with a VPN module. The hardware module will allow for more connections, but will also handle the connections a lot better.

How you want to set it all up and where to put your head end is up to you, but I think having the head end sit on the outside of your network just as your 877 does today is probably the easiest. In the links below you will find a lot of ways to do this, but the easiest is to use a head-end like you have now, but with beefier hardware.

Take out the spaces for those links and search the second one for "Easy VPN".

http://www.cisco.com/en/US/products/sw/secursw/ps5299/

http://www.cisco.com/en/US/docs/routers/access/800/850/software/configuration/guide/857sg_bk.pdf

http://www.cisco.com/en/US/prod/collateral/iosswrel/ps6537/ps6586/ps6635/prod_white_paper0900aecd803645b5.html

http://www.cisco.com/en/US/docs/ios/sec_secure_connectivity/configuration/guide/sec_easy_vpn_rem.html

http://www.cisco.com/en/US/docs/ios/sec_secure_connectivity/configuration/guide/sec_easy_vpn_srvr.html

Cisco – Using Cisco 877 Router with VDSL fibre optic connection

I've finally got it to work, here are the sections of my config which did it:

interface ATM0
 no ip address
 shutdown
 no atm ilmi-keepalive
 pvc 0/38 
  encapsulation aal5mux ppp dialer

interface FastEthernet0
!
interface FastEthernet1
!
interface FastEthernet2
 switchport access vlan 101
!
interface FastEthernet3
!
interface Vlan1
 description $ETH-SW-LAUNCH$$INTF-INFO-HWIC 4ESW$$FW_INSIDE$
 ip address 10.193.125.254 255.255.255.0
 ip nat inside
 ip virtual-reassembly
 zone-member security in-zone
!
interface Vlan101
 no ip address
 no ip redirects
 no ip unreachables
 no ip proxy-arp
 ip virtual-reassembly
 pppoe enable group global
 pppoe-client dial-pool-number 1
!
interface Dialer1
 description $FW_OUTSIDE$
 mtu 1492
 ip address negotiated
 no ip unreachables
 ip nat outside
 ip virtual-reassembly
 zone-member security out-zone
 encapsulation ppp
 dialer pool 1
 dialer-group 1
 no cdp enable
 ppp chap hostname 
 ppp chap password 0 
 ppp ipcp route default
!
ip forward-protocol nd
ip http server
ip http authentication local
ip http secure-server
ip http timeout-policy idle 60 life 86400 requests 10000
!
ip nat inside source list 1 interface Dialer1 overload
!
ip access-list extended NAT
 permit ip 10.193.125.0 0.0.0.255 any

Best Answer

Related Solutions

Cisco 877 – How to Use as a VPN Server

Cisco – Using Cisco 877 Router with VDSL fibre optic connection

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