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I was wondering if it was possible to use bit notatiton when configuring interfaces, or just in general, within the CISCO IOS. I have friends and others swear that they've been able to before, but not able to remember how. I get errors when attempting so I was thinking maybe there's a command to enable it if it's possible.


Router(config-router)# ip address /30
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That's actually called CIDR notation. – EEAA Jan 27 '12 at 14:34
up vote 2 down vote accepted

CIDR notation can be used in IOS on prefix-lists, but not on interface or routing protocol configuration. Cisco does support CIDR notation more broadly in NX-OS on the new Nexus products.

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