[c-nsp] 3750 Metro internal vlan allocation for loopback?

[Jared Gillis]

On 10/26/2011 09:58 AM, Peter Rathlev wrote:
> On Wed, 2011-10-26 at 09:41 +0200, Michele Bergonzoni wrote:
>> You might try to trade the Lo1 for a VLAN:
>>
>> vlan 4000
>> exit
>>
>> no spanning-tree vlan 4000
>>
>> int Vlan4000
>>   description Primary Management/Peering IP
>>   ip address a.b.c.d 255.255.255.255
> 
> I don't think SVIs can take /32 masks:

This appears to be the case. I tested as you did below on a lab 3750ME, and got the same error.

Along similar lines, I investigated to see whether it was possible to manually assign a VLAN id to the lo1 interface, but there does not seem to be any switchport or vlan-related commands available on that if:

gw.snrtcamn(config)#int loopback 1 
gw.snrtcamn(config-if)#?
Interface configuration commands:
  aaa                     Authentication, Authorization and Accounting.
  access-expression       Build a bridge boolean access expression
  arp                     Set arp type (arpa, probe, snap) or timeout or log options
  bandwidth               Set bandwidth informational parameter
  bgp-policy              Apply policy propagated by bgp community string
  carrier-delay           Specify delay for interface transitions
  cdp                     CDP interface subcommands
  clns                    CLNS interface subcommands
  dampening               Enable event dampening
  default                 Set a command to its defaults
  delay                   Specify interface throughput delay
  description             Interface specific description
  eou                     EAPoUDP Interface Configuration Commands
  exit                    Exit from interface configuration mode
  flow-sampler            Attach flow sampler to the interface
  help                    Description of the interactive help system
  history                 Interface history histograms - 60 second, 60 minute and 72 hour
  hold-queue              Set hold queue depth
  ip                      Interface Internet Protocol config commands
  isis                    IS-IS commands
  iso-igrp                ISO-IGRP interface subcommands
  keepalive               Enable keepalive
  link                    Configure Link
  load-interval           Specify interval for load calculation for an interface
  logging                 Configure logging for interface
  macro                   Command macro
  max-reserved-bandwidth  Maximum Reservable Bandwidth on an Interface
  mpls                    Configure MPLS interface parameters
  no                      Negate a command or set its defaults
  ntp                     Configure NTP
  rate-limit              Rate Limit
  routing                 Per-interface routing configuration
  service                 Configure Ether Service
  service-policy          Configure CPL Service Policy
  shutdown                Shutdown the selected interface
  snmp                    Modify SNMP interface parameters
  source                  Get config from another source
  spanning-tree           Spanning Tree Subsystem
  timeout                 Define timeout values for this interface
  topology                Configure routing topology on the interface
  traffic-shape           Enable Traffic Shaping on an Interface or Sub-Interface
  transmit-interface      Assign a transmit interface to a receive-only interface
  tx-ring-limit           Configure PA level transmit ring limit
  vrf                     VPN Routing/Forwarding parameters on the interface
  vtp                     Enable VTP on this interface


> Router(config)#vlan 4000
> Router(config-vlan)#name test
> Router(config-vlan)#exit
> % Applying VLAN changes may take few minutes.  Please wait...
> 
> Router(config)#int vlan 4000
> Router(config-if)#ip addr 192.0.2.1 255.255.255.255
> Bad mask /32 for address 192.0.2.1
> Router(config-if)#do sh run int vlan 4000
> Building configuration...
> 
> Current configuration : 51 bytes
> !
> interface Vlan4000
>  no ip address
>  shutdown
> end
> 
> Router(config-if)#
> 
> On a C6kSup720 running 12.2(33)SXI1 AIS. The 3750ME might behave
> differently.
>