HWIC limitation

Unanswered Question
Dec 2nd, 2008


I have a cisco 2811 with a hwic card (4-port FE Switch HWIC ). Is there any limitation in the configuration of that kind of hwic card ? Does it provide the same performance and command granularity than the two integrated fastethernet ports ?

I have this problem too.
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satish_zanjurne Tue, 12/02/2008 - 11:31


1.The 2 integrated FastEthernet ports are L3 ports.

2.Whereas the HWIC-4ESW or HWIC-4ESW-POE 4 port switch is L2 switch.

The modular 4- and 9-port Cisco EtherSwitch HWICs provide line-rate Layer 2 switching across Ethernet ports using Cisco IOS® Catalyst Software. The 4-port Cisco EtherSwitch HWIC has four 10/100 switched Ethernet ports, with options for inline power support on all four ports. The 9-port Cisco EtherSwitch HWIC has nine 10/100 switched Ethernet ports, with options for inline power support on 8 of the 9 ports. The ninth port does not support inline power but can be used as a regular switch port for trunking and other normal data applications. Note: The optional inline power support on the 4- and 9-port HWICs is offered on the Cisco 2800 and Cisco 3800 series. It is not offered on the Cisco 1841 of the Cisco 1800 Series (modular). Features such as port autosensing, quality of service (QoS), VLAN support from 802.1P and 802.1Q standards, and 802.1D spanning tree protocols are standard on the Cisco EtherSwitch HWIC. The Cisco EtherSwitch HWICs are available in standard 4- or 9-port 10/100BASE-TX switch HWIC and Power-over-Ethernet (PoE) configurations. The PoE configurations consist of a 4- or 9-port 10/100BASE-TX switch and a 4- or 8-port inline power module daughter card. The power module daughter card houses a power controller for detecting, classifying, and enabling power on 802.3af-compliant powered devices attached to the HWICs. The inline powered version of the Cisco EtherSwitch HWIC can power Cisco IP phones, Cisco wireless access points, or any other IEEE 802.3af-compliant device. The optional inline power support on the 4- and 9-port HWICs on the Cisco 2800 and Cisco 3800 series of integrated services routers requires the use of a field-replaceable inline power supply

Refer below link for more detail


HTH...rate if helpful..

Joseph W. Doherty Tue, 12/02/2008 - 12:37

Without doublechecking, I recall most Ethernet switch module Ehternet port interfaces present themselves differently from the built-in Ethernet ports. Believe the former requires ports be assigned to VLANs. (The HWIC-1FE or HWIC-1GE-SFP might appears as a built-in port, but I haven't configured one.)

With regard to performance, I also recall I once found mention of the bandwidth of HWIC slot. Gig bandwidth comes to mind, but I might be confusing HWIC slot bandwidth with NM slot bandwidth. However, the 2811 doesn't offer the performance to sustain FastEthernet performance on one port let alone multiple FastEthernet ports, so slot bandwidth isn't usually an issue.

mathieu.ploton Wed, 12/03/2008 - 00:27

Except the fact that there is a different way to configure it (assign each port to a vlan, make an interface vlan...), I just heard that the commands are not all available in that kind of interface (qos commands for example). Is it a mistake ?

Joseph W. Doherty Wed, 12/03/2008 - 03:34

I know there are a few command differences, for instance, believe you can only Etherchannel built-in ports. As for commands like QoS, unsure. It's been a while since I worked with a 2800 with a switch module. Don't believe I tried QoS on its interfaces, although it might be possible on the VLAN interfaces but not the underlying switch physical Ethernet interfaces. Perhaps someone else will comment further.


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