Provisioning WS-C3550-24PWR-SMI For Use With Polycoms

Provisioning WS-C3550-24PWR-SMI From Default Settings

Connect via console cable and configure hostname, telnet access and passwords using wizard at boot first time

Create voice and data vlan
3550(config)#vlan 2
3550(config-vlan)#name data
3550(config-vlan)# 790
3550(config-vlan)#name voice
Configure IP address on voice vlan
3550(config)#interface Vlan 790
3550(config-if)#ip address
Configure the default gateway
3550(config)# ip default-gateway
Configure gigbit ports as trunk ports to router or downstream switches
3550(config)#interface range gigabitEthernet 0/1 - 2
3550(config-if)# switchport trunk encapsulation dot1q
3550(config-if)# switchport trunk allowed vlan 2,790
3550(config-if)# switchport mode trunk
Configure 24 fastethernet ports as trunk ports for phones and/or computers. Vlan 790 will be tagged and vlan 2 (the native vlan) will be untagged. Note: the untagged vlan is called the "native vlan" when the switchport mode is "trunk". The untagged vlan is called the "access vlan" when the switchport mode is "access".
3550(config)#int range fastEthernet 0/1 - 24
3550(config-if-range)# switchport trunk encapsulation dot1q
3550(config-if-range)# switchport trunk native vlan 2
3550(config-if-range)# switchport mode trunk

Resolving Inline Power Issue

When using a WS-C3550-24PWR-SMI with a default config a Polycom 335 using POE cannot successfully boot up. During the bootup process just before the Polycom typically displays the networking information on the screen, the Polycom restarts its ethernet interface. By default the Cisco 3550 stops sending power to the port when it detects the link is down which causes the phone to lose power and restart. To remedy this problem the 3550 interface can be configured to delay turning off power to port for a defined number of seconds after it detects the link is down.

power inline delay {shutdown seconds initial seconds}

The initial time period begins when the powered device is detected by the switch. If linkdown occurs
on the connected device during the initial time period, the shutdown time determines
how long the switch continues to provide power to the device.
3550(config)# int range fastEthernet 0/1 - 24
3550(config-if-range)# power inline delay shutdown 20 initial 300
By applying the above command to an interface the switch will continue to provide power to the device 20 seconds after linkdown and the power shutdown delay will be in effect for the first 300 seconds. It may be necessary to upgrade IOS image to c3550-ipservicesk9-mz.122-44.SE6.bin as the power inline command is not available in older versions.

Upgrading the IOS image

Obtain a copy of the new IOS image and place on TFTP server. c3550-ipservicesk9-mz.122-44.SE6.bin will be used as an example. Note: an EMI image (enhanced software) can run on SMI hardware.

Show contents of flash and the space left (listed at the bottom)
Make sure there is enough room for the new ISO image
3550# dir flash:
Directory of flash:/
    2  -rwx        2177   Mar 01 1993 00:07:02  config.text
    3  -rwx           5   Mar 01 1993 00:07:02  private-config.text
    4  -rwx         676   Mar 01 1993 00:41:24  vlan.dat
   21  -rwx     3334765   Mar 02 1993 03:09:04  c3550-i9q3l2-mz.121-14.EA1a.bin
15998976 bytes total (6278656 bytes free)
To delete a file
3550# delete flash:c3550-i9q3l2-mz.121-14.EA1a.bin
Delete filename [c3550-i9q3l2-mz.121-14.EA1a.bin]?
Delete flash:c3550-i9q3l2-mz.121-14.EA1a.bin? [confirm]
 To see contents of a folder
3550# dir c3550-i5q3l2-mz.121-11.EA1
To delete a folder
3550# delete /force /recursive c3550-i5q3l2-mz.121-11.EA1
3550# Delete filename [c3550-i5q3l2-mz.121-11.EA1]?

Download and install IOS image. It should also update the boot statement
3550#copy tftp://tftp-server-ip/c3550-ipservicesk9-mz.122-44.SE6.bin flash://c3550-ipservicesk9-mz.122-44.SE6.bin
Verify the image was corrupted in transfer
3550#verify /md5 flash:c3550-ipservicesk9-mz.122-44.SE6.bin
verify /md5 (flash:c3550-ipservicesk9-mz.122-44.SE6.bin) = a829d14ab1ccd3ecf77b99d025d188ce
Tell the switch to use the new IOS image
3550(config)#boot system flash:c3550-ipservicesk9-mz.122-44.SE6.bin
Confirm the new boot statement is correct
3550 # show boot
BOOT path-list:       flash:c3550-ipservicesk9-mz.122-44.SE6.bin
Config file:          flash:/config.text
Private Config file:  flash:/private-config.text
Enable Break:         no
Manual Boot:          no
HELPER path-list:  
NVRAM/Config file
      buffer size:    393216
Save any changes made to the config
3550#copy running-config startup-config
Destination filename [startup-config]?
Building configuration...
Restart the switch
After restart, confirm switch is running new IOS
3550# show version
Cisco IOS Software, C3550 Software (C3550-IPSERVICESK9-M), Version 12.2(44)SE6, RELEASE SOFTWARE (fc1)
System image file is "flash:c3550-ipservicesk9-mz.122-44.SE6.bin"


Hardeep said...

I know this is very old post and if i am commenting on a 3550 switch power inline delay i am probably leaving under some rock for the past five years, but sometime some old stuff still gets your work done for testing purpose without investing in new switch, thanks for sharing your experience on a Cisco WS-C3550-24PWR-SMI power inline delay setting.

Post a Comment