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Re : SIP MAC Address ...


I need some assistance on the following : -

i) What is a SIP MAC Addreess within a switch/router ?

ii) how does a switch detects a spoofed mac address ?

iii) how do I check for the highest MAC address flow count inside a switch/router

Thank you,


- InternetB -

Hall of Fame Super Silver

Re: Re : SIP MAC Address ...

Hello InternetB,

i) not enough clear

however SIPs are modules that can be installed on C7600.

So check with sh module if there is a SIP module (they are the ones that support SPAs) installed

See the following example from a C7606 with a SIP

sh module

Mod Ports Card Type Model Serial No.

--- ----- -------------------------------------- ------------------ -----------

1 24 CEF720 24 port 1000mb SFP WS-X6724-SFP SAL1049A78R

2 48 CEF720 48 port 10/100/1000mb Ethernet WS-X6748-GE-TX SAL10436CED

3 0 4-subslot SPA Interface Processor-400 7600-SIP-400 JAB104802PV

6 2 Supervisor Engine 720 (Active) WS-SUP720-3BXL SAL10467RED

Mod MAC addresses Hw Fw Sw Status

--- ---------------------------------- ------ ------------ ------------ -------

1 0019.56f3.7794 to 0019.56f3.77ab 2.5 12.2(14r)S5 12.2(33)SRC Ok

2 0019.aa75.1138 to 0019.aa75.1167 2.5 12.2(14r)S5 12.2(33)SRC Ok

3 001a.6d7e.c800 to 001a.6d7e.c87f 2.3 12.2(33)SRC 12.2(33)SRC Ok

6 0017.9444.1140 to 0017.9444.1143 5.2 8.4(2) 12.2(33)SRC Ok

Mod Sub-Module Model Serial Hw Status

---- --------------------------- ------------------ ----------- ------- -------

1 Distributed Forwarding Card WS-F6700-DFC3BXL SAL1045772E 5.3 Ok

2 Distributed Forwarding Card WS-F6700-DFC3BXL SAL1046824X 5.3 Ok

3/0 1xOC48 POS/RPR SPA SPA-1XOC48POS/RPR JAB104002UT 2.2 Ok

6 Policy Feature Card 3 WS-F6K-PFC3BXL SAL10467S8K 1.8 Ok

6 MSFC3 Daughterboard WS-SUP720 SAL10467UYH 2.5 Ok

ii) it cannot it can just notify that a MAC address is flapping between two ports: this can be a sign of a loop or of a server with NIC teaming

iii) sh mac-address-table count


sh mac-address-table count

MAC Entries for all vlans :

Dynamic Address Count: 83

Static Address (User-defined) Count: 299

Total MAC Addresses In Use: 382

Total MAC Addresses Available: 65536

this is from a 7606

Hope to help


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