This script will put me in my grave. I have a file that looks like this: 
 address-family ipv4 vrf V1234:ABCD
 neighbor 192.168.254.2 route-map something in
 neighbor 192.168.254.2 route-map something out

 address-family ipv4 vrf V8765:ZYXW
 neighbor 192.168.254.6 route-map something in
 neighbor 192.168.254.6 route-map something out

 address-family ipv4 vrf V0918:AZBY
 neighbor 192.168.254.10 route-map something in
 neighbor 192.168.254.10 route-map something out

[download]
What I need to do is decrement the last octet of each IP address by one, so it looks like this: 
 address-family ipv4 vrf V1234:ABCD
 neighbor 192.168.254.1 route-map something in
 neighbor 192.168.254.1 route-map something out

 address-family ipv4 vrf V8765:ZYXW
 neighbor 192.168.254.5 route-map something in
 neighbor 192.168.254.5 route-map something out

 address-family ipv4 vrf V0918:AZBY
 neighbor 192.168.254.9 route-map something in
 neighbor 192.168.254.9 route-map something out

[download]
I have tried several variations with 'sed', but can't get anywhere. Any ideas?

In reply to decrementing numbers by ddrew78

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