Trunk configuration methods
Dynamic LACP trunk
The switch automatically negotiates trunked links
between LACP-configured ports on separate devices, and offers one
dynamic trunk option: LACP. To configure the switch to initiate a
dynamic LACP trunk with another device, use the interface command
in the CLI to set the default LACP option to active on
the ports you want to use for the trunk. For example, the following
command sets ports C1 to C4 to LACP active:
The preceding Example: works if the ports are not already operating in a trunk. To change the LACP option on ports already operating as a trunk, you must first remove them from the trunk. For example, if ports C1 to C4 are LACP-active and operating in a trunk with another device, you would do the following to change them to LACP-passive:
Removes the ports from the trunk.
Configures LACP passive.
Static trunk
The switch uses the links you configure with
the Port/Trunk Settings screen in the menu interface or the trunk command
in the CLI to create a static port trunk. The switch offers two types
of static trunks: LACP and Trunk.
Trunk types used in static and dynamic trunk groups
| Trunking method | LACP | Trunk |
|---|---|---|
| Dynamic | Yes | No |
| Static | Yes | Yes |
Trunk configuration protocols describes the trunking options for LACP and Trunk protocols.
Trunk configuration protocols
| Protocol | Trunking Options |
|---|---|
| LACP (802.3ad) | Provides dynamic and static LACP trunking options.
For more information, see Trunk group operation using LACP. |
Trunk |
Provides manually configured, static-only trunking to:
Use the Trunk option when:
|
General operating rules for port trunks
| Media: | For
proper trunk operation, all ports on both ends of a trunk group must
have the same media type and mode (speed and duplex). (For the switches,
HPE Switch recommends leaving the port Mode setting at | ||||||
| Port Configuration: | The default port configuration is
Recommended port mode setting for LACP HP Switch(config)# show interfaces config Port Settings Port Type | Enabled Mode Flow Ctrl MDI ----- --------- + ------- ------------ --------- ---- 1 10/100TX | Yes Auto Enable Auto 2 10/100TX | Yes Auto Enable MDI All of the following operate on a per-port basis, regardless of trunk membership:
LACP is a full-duplex protocol. See Trunk group operation using LACP. | ||||||
| Trunk configuration: | All ports in the same trunk group must be the same trunk type (LACP or trunk). All LACP ports in the same trunk group must be either all static LACP or all dynamic LACP. A trunk
appears as a single port labeled For spanning-tree or VLAN operation, configuration for all ports in a trunk is done at the trunk level. (You cannot separately configure individual ports within a trunk for spanning-tree or VLAN operation.) | ||||||
| Traffic distribution: | All of the switch trunk protocols use the SA/DA (source address/destination address) method of distributing traffic across the trunked links. See Outbound traffic distribution across trunked links. | ||||||
| Spanning Tree: | 802.1D (STP) and 802.1w (RSTP) Spanning Tree operate as a global setting on the switch (with one instance of Spanning Tree per switch). 802.1s (MSTP) Spanning Tree operates on a per-instance basis (with multiple instances allowed per switch). For each Spanning Tree instance, you can adjust Spanning Tree parameters on a per-port basis. A static trunk of any type appears in the Spanning Tree configuration display, and you can configure Spanning Tree parameters for a static trunk in the same way that you would configure Spanning Tree parameters on a non-trunked port. (Note that the switch lists the trunk by name—such as Trk1—and does not list the individual ports in the trunk.) For example, if ports C1 and C2 are configured as a static trunk named Trk1, they are listed in the Spanning Tree display as Trk1 and do not appear as individual ports in the Spanning Tree displays. See A port trunk in a Spanning Tree listing. When Spanning Tree forwards on a trunk, all ports in the trunk will be forwarding. Conversely, when Spanning Tree blocks a trunk, all ports in the trunk are blocked.
If you remove a port from a static trunk, the port retains the same Spanning Tree settings that were configured for the trunk. In the below Example:, ports C1 and C2 are members of TRK1 and do not appear as individual ports in the port configuration part of the listing.
A port trunk in a Spanning Tree listing Port Type Cost Priority State | Designated Bridge ----- --------- ---- -------- ---------- + ----------------- C3 100/1000T 5 12B Forwarding | 0020c1-b27ac0 C4 100/1000T 5 12B Forwarding | 0060b0-889e00 C5 100/1000T 5 12B Disabled | C6 100/1000T 5 12B Disabled | Trk1 1 64 Forwarding | 0001e7-a0ec00 | ||||||
| IP multicast protocol (IGMP): | A static trunk of any type appears in the IGMP configuration display, and you can configure IGMP for a static trunk in the same way that you would configure IGMP on a non-trunked port. (Note that the switch lists the trunk by name—such as Trk1—and does not list the individual ports in the trunk.) Also, creating a new trunk automatically places the trunk in IGMP Auto status if IGMP is enabled for the default VLAN. A dynamic LACP trunk operates only with the default
IGMP settings and does not appear in the IGMP configuration display
or | ||||||
| VLANs: | Creating a new trunk automatically places the trunk in the DEFAULT_VLAN, regardless of whether the ports in the trunk were in another VLAN. Similarly, removing a port from a trunk group automatically places the port in the default VLAN. You can configure a static trunk in the same way that you configure a port for membership in any VLAN.
| ||||||
| Port security: | Trunk
groups (and their individual ports) cannot be configured for port
security, and the switch excludes trunked ports from the | ||||||
| Monitor port: |
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