The "Extreme Extended Edge" solution (also known as the Virtual Port Extender - VPEX) is a new technology that was first introduced in the EXOS operating system with the 22.5 release. The solution is based on the IEEE 802.1BR (Bridge Port Extension) standard, and the ExtremeSwitching V400 hardware line was supported in the EXOS 22.5 release.
"VPEX Bridge" is a virtual switch consisting of components such as the Controlling Bridge (CB) and the Bridge Port Extender (BPE). For resilience, it is possible to connect to two CBs within one virtual switch using MLAG technology. The design of such a virtual switch resembles a classic chassis switch or a stack of switches. While the logic of the Control Plane is more or less consistent with this, the functioning of the Data Plane differs significantly. The purpose of 802.1br is to connect a remote port to a local Media Access Control (MAC) service while isolating the traffic from remote ports.
Controlling Bridge
- A single point of control
- All configuration occurs locally on the CB
- VPEX support must be activated; a reboot is required to change the operating mode
- CB is always slot No. 1
- In the current release, the CB supports simultaneous connection of up to 48 BPEs
- The CB mode is supported on certain hardware platforms (currently X670G2 and X690; other platforms will be added as they become available)
- EXOS licenses apply only to the CB
- VPEX does not require additional licenses
- Fully responsible for data-plane traffic processing and filtering
- Contains a virtual representation of each "extended" port
Bridge Port Extender
- BPE devices are managed like slots in a chassis switch
- BPE slots are numbered from 100 to 162
Slot-1 VPEX X690-48x-2q-4c.3 # show slot
Slots Type Configured State Ports Flags
-------------------------------------------------------------------------------
Slot-1 X690-48x-2q-4c X690-48x-2q-4c Operational 72 M
Slot-100 V400-48t-10GE4 V400-48t-10GE4 Operational 52 M
Slot-101 V400-48t-10GE4 V400-48t-10GE4 Operational 52 M
Slot-102 V400-48t-10GE4 V400-48t-10GE4 Operational 52 M
Slot-103 V400-48t-10GE4 V400-48t-10GE4 Operational 52 M
- There is no need for console or Out-of-Band IP connection to the BPE
- All configuration, monitoring, troubleshooting, and diagnostics are carried out through the CB interface
Slot-1 VPEX X670G2-48x-4q.8 # config vlan v100 add port 100:1,100:3
*Slot-1 VPEX X670G2-48x-4q.9 # show port 100:1-3 statistics no-refresh
Port Link Tx Pkt Tx Byte Rx Pkt Rx Byte Rx Pkt Tx Pkt
State Count Count Count Count Mcast Mcast
====== ===== ========== =========== ========== =========== ======= ========
100:1 A 2126523437 >9999999999 0 0 0 14383
100:2 R 0 0 0 0 0 0
100:3 A 21824 4759804 2126738453 >9999999999 0 14383
====== ===== ========== =========== ========== =========== ======= ========
- BPE do not perform local switching. As a result, all traffic is tunneled to the CB and, if necessary, forwarded to the adjacent port of the same BPE slot, returned back. (BPE takes the packet, adds an E-TAG header, and sends it to the upstream port)
A new hardware platform, ExtremeSwitching V400, has been introduced to function as BPE. It includes port expanders for 24/48 10/100/1000 Base-T ports with or without PoE support. In the 24-port models, there are two 10G ports, and in the 48-port models, there are four 10G ports.
Operation Features
Topologies with one or two CBs and up to four cascaded VRE in a chain are supported. Cascaded ports can be combined into a LAG (up to 4 ports for V400-48t/p models). End stations can connect to various BPE slots using LAG.
BPE detection and operation are based on protocols such as:
- LLDP – initial detection and identification of the type and capabilities of the connected device
- ECP – 'Edge Control Protocol', transport for PE-CSP
- PE-CSP – 'Port Extender Control and Status Protocol', configuration control of BPE with the Controlling Bridge
- LACP – establishing a LAG between 'cascade' 'upstream' ports
If a resilient design with two CBs and MLAG is used, when one CB is rebooted, the BPE will continue to send traffic through the remaining Controlling Bridge. If the only CB is rebooted, the BPE will administratively disable its 'extended' ports.
For ease of configuring a topology with 2 CBs, the ability to configure MLAG ports of both peers from any of the CBs has been added. This mode is called 'mlag orchestration', during which the peers synchronize part of the config relating to MLAG port settings. The configuration resembles that of user 'virtual-router'.
Slot-1 VPEX X670G2-48x-4q.11 # start orchestration mlag "bottom"
(orchestration bottom) Slot-1 VPEX X670G2-48x-4q.12 # exit
Slot-1 VPEX X670G2-48x-4q.13 #
The functionality of the 'Controlling Bridge' is available after installing a free module for EXOS that has the .xmod extension. This same module contains update images for the BPE. When the SV and BPE detect each other, CB checks the firmware version installed on the BPE and automatically updates it if necessary.
The above-mentioned features allow for a straightforward and quick replacement of the BPE slot when needed. Since BPE slots do not store the configuration and are not tied to the system, immediately after replacing the device and powering it on, the BPE will be detected by the SV and the existing configuration will be applied. Additionally, if necessary, the firmware will be updated.
This solution is well-suited for networks with a predominant North/South traffic direction, such as campus networks, enterprise networks in logistics, education, business centers, and others. To reiterate, the advantages of networks built on the 'Extreme Extended Edge' solution will include:
- Reduction of levels in traditional network architecture from a configuration and management perspective
- Simplicity of scaling and deployment
- No need for dedicated console or out-of-band Mgmt connections to the BPE slots
- Reduction in licensing (if necessary, applicable only to SV)
- A single point for configuration, monitoring, and troubleshooting
- Displayed in NMS as a single switch
- No need for additional training and staff expansion
Source: habr.com
