Combination Ports

The two 10/100/1000 ports are combination ports. When an SFP module is inserted it has priority over the 10/100/1000 port of the same number. The corresponding 10/100/1000 port is disabled. The combination ports are numbered 25-26 on the Switch 3226 and 49-50 on the Switch 3250.

Supported SFP Modules

3CSFP91 — SFP 1000BASE–SX

3CSFP92 — SFP 1000BASE–LX

3CSFP97 — SFP 1000BASE–LH70

Start-up Time

The unit will take approximately 2 minutes to become fully operational. The unit is fully operational when the Self Test LED is lit solid green

Autonegotiation of Port Speed and Duplex

All ports on the unit default to using autonegotiation to determine the correct speed and duplex setting. If the link partner also supports autonegotiation then this will result in the optimum link speed and duplex.

The speed and duplex of the port may be manually set by using the physicalInterface ethernet portMode command to disable autonegotiation and select a fixed speed and duplex.

When autonegotiation is enabled, the unit asks for a fallback mode to be entered for use when the port connects to a non-autonegotiation device. This fallback mode parameter has been left in the CLI for

Points to Note when using the Switch 3226 and Switch 3250

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compatibility with other 3Com devices but is ignored by this device.

When connected to a device that will not autonegotiate the device follows the algorithm required by the autonegotiation standard which states that ports must detect the link speed and then operate in half duplex mode.

Auto-MDIX is not available if auto-negotiation is disabled on a port. That port will only operate in MDIX mode.

LACP Protocol

The LACP protocol is disabled by default. Some legacy devices do not support LACP and 3Com strongly recommends LACP remains disabled on ports connected to these devices (in rare cases, if LACP is enabled on ports connected to these devices, it can result in incorrect network configurations).

Web Interface

Many Web browsers can be configured to ignore stylesheets, substituting user configured fonts and font sizes. Ignoring stylesheets may cause unpredictable effects when accessing the Web interface. 3Com recommends that you enable stylesheets on browsers used to access the Web interface of the Switch.

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3Com 3250 Combination Ports, Supported SFP Modules, Start-up Time, Autonegotiation of Port Speed and Duplex, Lacp Protocol