IP Phones Added to the Community Lab

By stretch | Wednesday, September 22, 2010 at 5:28 p.m. UTC

A reader by the name of Robert Juric generously donated four Cisco 7940 IP phones to the lab! I just finished connecting them to switches S3 and S4 and they're ready for use. I've also updated the lab topology to reflect their addition.

lab_topology_ethernet.png

Power is supplied to all four phones by Cisco's legacy (pre-IEEE 802.3af) PoE implementation known as inline power (ILP). The phones have been left with their factory default configurations, which means they will look for IP addresses via DHCP. (Any of the IOS routers can be configured to act as a DHCP server.)

The following outputs were taken from S3.

Switch# show power inline
Available:360(w)  Used:12(w)  Remaining:348(w)

Interface Admin  Oper       Power   Device              Class Max
                            (Watts)                            
--------- ------ ---------- ------- ------------------- ----- ----
Fa0/1     auto   off        0.0     n/a                 n/a   15.4 
Fa0/2     auto   off        0.0     n/a                 n/a   15.4 
Fa0/3     auto   off        0.0     n/a                 n/a   15.4 
Fa0/4     auto   off        0.0     n/a                 n/a   15.4 
Fa0/5     auto   off        0.0     n/a                 n/a   15.4 
Fa0/6     auto   off        0.0     n/a                 n/a   15.4 
Fa0/7     auto   off        0.0     n/a                 n/a   15.4 
Fa0/8     auto   off        0.0     n/a                 n/a   15.4 
Fa0/9     auto   off        0.0     n/a                 n/a   15.4 
Fa0/10    auto   off        0.0     n/a                 n/a   15.4 
Fa0/11    auto   on         6.3     IP Phone 7940       n/a   15.4
Fa0/12    auto   on         6.3     IP Phone 7940       n/a   15.4
Fa0/13    auto   off        0.0     n/a                 n/a   15.4 
Fa0/14    auto   off        0.0     n/a                 n/a   15.4 
Fa0/15    auto   off        0.0     n/a                 n/a   15.4 
Fa0/16    auto   off        0.0     n/a                 n/a   15.4
...

Switch# show cdp neighbor f0/11 detail
-------------------------
Device ID: SEP0013197E4F88
Entry address(es): 
Platform: Cisco IP Phone 7940,  Capabilities: Host 
Interface: FastEthernet0/11,  Port ID (outgoing port): Port 1
Holdtime : 128 sec

Version :
P00307020200

advertisement version: 2
Duplex: full
Power drawn: 6.300 Watts
Management address(es): 

About the Author

Jeremy Stretch is a network engineer living in the Raleigh-Durham, North Carolina area. He is known for his blog and cheat sheets here at Packet Life. You can reach him by email or follow him on Twitter.

Posted in Announcements

Comments


joshlowe
September 23, 2010 at 1:41 p.m. UTC

I hoped you turned the ringers off! :)


dps218
September 23, 2010 at 2:39 p.m. UTC

Great, next you can add support personnel whom we can call on a 24 hours basis!


kasmot
October 18, 2010 at 2:15 p.m. UTC

thanks sir. this is a great help.

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