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Over the weekend Dominik and myself had a great conversation with Roger Lapuh, Product Line Manager and Architect at Avaya. We recorded the conversation and posted it up to the Network Broadcast Storm podcast.
If your interested in some of the back story behind SMLT you might find the conversation interesting.
Cheers!
I get asked quite frequently to explain what is a MLT, DMLT, SMLT, SLT or IST are and how they work.
Let me start with some definitions and then we’ll move on from there;
You can use MLT or DMLT between two switches in what I would refer to as a traditional trunking application. A Distributed MultiLink Trunk provides additional redundancy by spreading the links out across multiple line cards or switches in a stack depending on the switch model/configuration. An MLT/DMLT is Avaya’s proprietary equivalent to Cisco’s EtherChannel or PortChannel feature. An Avaya MLT or DMLT configuration can interoperate with Cisco’s EtherChannel or PortChannel configuration.
It’s important to point out that Avaya switches will (by default) only send out BPDU frames on the lowest number if index of a MLT or DMLT trunk. This can be overridden in newer software releases with the command “mlt 1 bpdu all-ports“. Cisco switches will send out BPDU frames on all ports in an EtherChannel or PortChannel configuration.
You can use SMLT or SLT between two cluster switches and a single edge/distribution switch or stack essentially creating a triangle topology without the need for Spanning Tree. Both links between the core and edge/distribution are actively forwarding traffic. An SMLT/SLT is Avaya’s proprietary equivalent to Cisco’s Virtual PortChannel feature. When do you use one over the other, SMLT or SLT? The later software releases only allowed between 32 and 64 MLTs per switch. If you had more than 31 edge switches you would run out of available MLTs, so Avaya came up with SLT – you can have as many SLTs as you have ports in the switch. SMLT will allow you to bond between 2 and 8 ports into a single virtual trunk on each cluster switch while SLT is designed to allow two ports max (one per cluster switch).
It’s important to note that you can utilize LACP with MLT, DMLT or SMLT ports just a you can with PortChannel groups.
The majority of closets I deploy utilizing SLT in the cluster core although there are a few closets that require more than 2 x 1Gbps uplinks so for those we utilize a SMLT configuration allowing up to 16 x 1Gbps links between the core cluster switches and edge/distribution switches.
Spanning Tree Protocol and IST/SMLT
Avaya has not extended the functionality of the Spanning Tree Protocol to run over an IST/SMLT topology. You can’t run STP between your core cluster switches and your edge switch/stack. That doesn’t mean that we can abandon STP altogether. It’s critical that Spanning Tree be utilized on all the edge ports in FastStart (PortFast) mode to eliminate the possibility of anyone accidentally creating a loop between any two ports in the edge switch. I also recommend that BPDU filtering be enabled on all edge ports along with Broadcast and Multicast rate-limiting.
Virtual Link Aggregation Control Protocol (VLACP)
In an Avaya network there is a special secret sauce that helps to bring everything together providing timely failure detection and recovery in an MLT, DMLT, IST, SMLT and SLT topology. VLACP is a lightweight heartbeat protocol utilized between two Avaya switches to detect Layer 2 connectivity issues between two endpoints. The trick these days isn’t detecting a failure but knowing when to restore a failed path taking into account the time it takes to rebuild routing and forward tables. VLACP is an Avaya proprietary protocol so it will only work between two Avaya switches.
If you’d like to know more about VLACP or how to configure it you can read my article entitled, Is VLACP right for me?
Cheers!
It was recently pointed out to me that I had never written a post documenting how to configure SMLT to a edge/closet switch. While there are plenty of examples in the Avaya/Nortel technical guides I’ll humor the folks that are interested. In this example I’ll configure a pair of ERS 8600 switches utilizing SMLT over SLT (Single Link Trunks).
Let’s assume that these switches are already setup in an IST pair (future post?) and that we want to add a new edge/closet switch to the network. We’ll utilize port 1/7 on both ERS 8600 switches to connect to ports 1/47 and 1/48 on the edge switch. The edge switch should be setup as an MLT. You can refer to this post for additional details regarding how to configure the edge switch.
Here’s a diagram of our example topology…
Let’s start configuring the ERS8600-A switch;
config ethernet 1/7 perform-tagging enable config ethernet 1/7 untagged-frames-discard enable config ethernet 1/7 default-vlan-id 200 config ethernet 1/7 cp-limit enable multicast-limit 7500 broadcast-limit 5000 config ethernet 1/7 enable-diffserv true config ethernet 1/7 slpp packet-rx enable config ethernet 1/7 slpp packet-rx-threshold 5 config ethernet 1/7 mstp cist forceportstate disable config ethernet 1/7 mstp msti 1 forceportstate disable config ethernet 1/7 smlt 107 create config ethernet 1/7 vlacp enable config ethernet 1/7 vlacp fast-periodic-time 500 config ethernet 1/7 vlacp timeout short config ethernet 1/7 vlacp timeout-scale 5
Let’s break down those commands and review each;
This command will enable tagging to make the port an 802.1q trunk port. This will enable us to trunk multiple VLANs over the single interface, it will also preserve an Layer 2 QoS/CoS information.
This command will discard any non 802.1q tagged frames that are received on the port. This can be a valuable defense measure in protecting your network. What would happen if the edge switch was accidentally factory reset with both uplinks still connected? A loop would result, however, with this feature all frames from the edge switch will be discarded until the switch is reconfigured.
This command will set the PVID to our management VLAN. This value will only be considered if the port receives a frame which doesn’t have an 802.1q header and hence is missing the VLAN ID. The command “untagged-frames-discard enable” essentially negates this command but we set it anyway so we’re consistent in our configurations.
This command will enable CP-Limit to protect the core network from too many Multicast or broadcast packets flooding the link. CP-Limit will shutdown the link to try and protect the core network. This is just one of many defense mechanisms available to help protect your network.
This command will enable DiffServ (Layer 3 QoS) on the switch port and set it for Trusted, so the switch will honor all DiffServ marked packets and give those packets the appropriate priority and queuing.
These commands will enable Simple Loop Protection Protocol (SLPP) to help detect any misconfiguration of the MultiLink trunks on the edge/closet switch.
These commands will disable Multiple Spanning Tree Protocol (MSTP) no the switch ports. Spanning Tree is not compatible with Avaya’s Split Trunking Protocol since we are quite literally creating a loop in the physical topology. If this switch was running STP the command would like so, ethernet 1/7 stg 1 stp disable.
Here’s the command that you’ve been waiting for … this command essentially creates a S-SMLT or Single Link Trunk (SLT). The ID used in the connection needs to match the peer ERS 8600 switch.
Design note – in my networks I use numbers to denote the different IDFs or ICRs. I usually add 100 to those numbers for the SMLT ID and VLAN IDs. Since this is IDF #7 (or ICR #7) the SMLT ID is 100 + 7 = 107 and the VLAN for this closet will eventually be 107. If I was still using VRRP the VRRP ID would also be 107. You can use whatever number you’d like but they must match on the two ERS 8600s!
These commands enable VLACP on the port and utilize the recommended values from Avaya.
You should repeat the commands above in Step 1 on both Avaya Ethernet Routing Switch 8600s, substitute the appropriate port numbers and SMLT ID.
Design note – in my networks the edge/closet switches are still Layer 2 only so I perform all the routing in the core switches. I will usually have a “default” VLAN per edge/closet switch although I do have multiple VLANs that span multiple edge/closet switches.
With the port configured now we’ll build the VLAN that we’ll associate with most ports on the edge switch.
config vlan 107 create byport-mstprstp 1 name "10-1-112-0/23" config vlan 107 add-mlt 1 config vlan 107 ports add 1/7 member portmember config vlan 107 fdb-entry aging-time 21601 config vlan 107 ip create 10.1.112.1.1/255.255.254.0 mac_offset 0 config vlan 107 ip igmp proxy-snoop enable config vlan 107 ip igmp snoop enable config vlan 107 ip dhcp-relay enable config vlan 107 ip ospf interface-type passive config vlan 107 ip ospf enable config vlan 107 ip rsmlt enable config vlan 107 ip rsmlt holdup-timer 9999
Let’s break down those commands and review each;
This command will create VLAN 107 and make it a port based VLAN with the name “10-1-112-0/23”. You might be asking what the mstprstp is… this specific switch I’m working with has been deployed with MSTP enabled. If you have a switch still using STP (default) then the command would look like so config vlan 107 create byport 1 name “10-1-112-0/23”
This command will add VLAN 107 to our IST which in this case happens to be MLT ID 1.
This command will add VLAN 107 to port 1/7 which we are using to connect our edge/closet switch.
This command will set the default FDB aging time for all MAC information learned in this VLAN to 6 hours and 1 second. This is a best practice recommendation by Avaya to help reduce the ARP broadcast storms that can result when the FDB table expires a large number of entries which then in turn causes them to be removed from the ARP table causing the switch to re-ARP for them.
This command will configure a Layer 3 interface on VLAN 107 with the IP address of 10.1.112.1/23. Your mac_offset will differ depending on how many IP interfaces you already have deployed on your switch.
This command will enable IGMP snooping and proxy on the VLAN.
These commands will enable DHCP relay on the VLAN, and forward all DHCP requests to 10.1.1.100.
This command will enable OSPF on the VLAN and will set it to passive (best practice for edge/closet VLANs).
This command will enable RSMLT which replaces the VRRP functionality. We set the holdup-timer to infinity, we don’t want the ERS 8600 to stop accepting packets for it’s peer at anytime.
You should repeat the commands above in Step 2 on both Avaya Ethernet Routing Switch 8600s, substitute the appropriate IP address and ports.
There are a few items that we still need to take care of to round out the configuration.
We need to enable SLPP for VLAN 107;
These commands will enable SLPP globally and will also enable SLPP in VLAN 107.
Here are some commands you can use to verify the configuration and operation.
You can check the SMLT table and verify that the trunk is configured as SMLT and operating as SMLT;
ERS-8610-A:5# show smlt info ================================================================================ Mlt SMLT Info ================================================================================ MLT SMLT ADMIN CURRENT ID ID TYPE TYPE -------------------------------------------------------------------------------- 4 4 smlt smlt 10 10 smlt norm 15 15 smlt norm ================================================================================ Port SMLT Info ================================================================================ PORT SMLT ADMIN CURRENT NUM ID TYPE TYPE -------------------------------------------------------------------------------- 1/7 3 smlt smlt 4/4 6 smlt smlt
You can check the MLT table and verify that VLAN 107 is a member of MLT 1 (IST);
ERS-8610-A:5# show mlt info ================================================================================ Mlt Info ================================================================================ PORT SVLAN MLT MLT PORT VLAN MLTID IFINDEX NAME TYPE TYPE ADMIN CURRENT MEMBERS IDS -------------------------------------------------------------------------------- 1 6144 MLT-IST trunk normal ist ist 1/1,4/1,8/1 1 2 3 4 5 9 10 20 21 25 99 100 101 102 103 107 198 199 200
You can verify that the IST is up and operational between the two ERS 8600 switches;
ERS-8610-A:5# show mlt ist info ================================================================================ Mlt IST Info ================================================================================ MLT IP VLAN ENABLE IST ID ADDRESS ID IST STATUS -------------------------------------------------------------------------------- 1 10.1.100.2 100 true up
You can check the state of VLACP on port 1/7 to confirm that VLACP is enable and up.
ERS-86010-A:5# show port info vlacp port 1/7 ================================================================================ VLACP Information ================================================================================ INDEX ADMIN OPER PORT FAST SLOW TIMEOUT TIMEOUT ETHER MAC ENABLED ENABLED STATE TIME TIME TIME SCALE TYPE ADDR -------------------------------------------------------------------------------- 1/7 true true UP 500 30000 short 5 0x8103 01:80:c2:00:11:00
You can check the SONMP topology tables to make sure you have the correct port(s).
ERS-8610-A:5# show sys topology ================================================================================ Topology Table ================================================================================ Local Rem Port IpAddress SegmentId MacAddress ChassisType BT LS CS Port -------------------------------------------------------------------------------- 0/0 10.1.1.1 0x000000 0004387xxxxx ERS8610 12 Yes HtBt 0/0 1/1 10.1.1.2 0x000101 000fcdfxxxxx ERS8610 12 Yes HtBt 1/1 1/7 10.1.255.20 0x00012f 0014c73xxxxx mBayStack5520-48T-PWR 12 Yes HtBt 1/47
Cheers!
There was a question recently on the discussion forums regarding the ability to run Spanning Tree Protocol (STP/RSTP/MSTP) over a MultiLink Trunk (MLT). You can most certainly run STP/RSTP/MSTP over a MLT interface. You can NOT run STP/RSTP/MSTP over a SMLT interface.
I thought I would run through a few quick commands to demonstrate how to enable Spanning Tree over an MLT interface. In the spirit of making things interesting I’ll utilize Multiple Spanning Tree Protocol (MSTP) over the default legacy Spanning Tree Protocol (STP) or the optional Rapid Spanning Tree Protocols (RSTP). I won’t try to explain Spanning Tree as there are plenty of resources available on the Internet.
For this example I have an Avaya Ethernet Routing Switch 5520 and an Avaya Ethernet Switch 460 (formerly Nortel BayStack 460). I’ll setup 2 MLT links between the two switches utilizing 4 ports in total. I’ll utilize VLANS 1, 100, 200 and Multiple Spanning Tree Instances (MSTI) 1 and 2 with CIST 0.
By default only legacy STP is enabled so we need to enable MSTP and reload the switch;
config t spanning-tree mode mst copy config nvram boot -y
Once the switch has restarted we can continue the configuration. Let’s make all 4 ports 802.1q tagged ports;
config t vlan ports 11,12,17,18 tagging tagAll
Now we’ll create the MultiLink Trunk interfaces and add the port members. You might notice in the code below the command “mlt # bpdu all-ports”. By default Avaya/Nortel switches only send BPDU frames on the single port in a MLT. This is completely opposite of the behavior from Cisco and other network manufacturers so as a best practice I enable this option. If we were connecting Avaya switches and didn’t enable this feature we would need to ensure that the lowest number ifIndex on one switch connected to the lowest number ifIndex on the other switch. This is important because Nortel/Avaya switches only send BPDU frames on the lower ifIndex port in an MLT. For example if we had say ports 3 and 7 on switch A and ports 10 and 14 on switch B we would need to connect 3(A) to 10(B) and 7(A) to 14(B) to ensure that the BPDU frames would be exchanged on matching ports between the switches.
mlt 1 name "Primary Group" mlt 1 member 11,12 mlt 1 learning enable mlt 1 bpdu all-ports mlt 1 enable mlt 2 name "Secondary Group" mlt 2 member 11,12 mlt 2 learning enable mlt 2 bpdu all-ports mlt 2 enable
Now we’ll create the MSTI instances 1,2 along with VLANS 100,200 respectively;
spanning-tree mstp msti 1 spanning-tree mstp msti 1 enable spanning-tree mstp msti 2 spanning-tree mstp msti 2 enable spanning-tree mstp region region-name acme region-version 1 spanning-tree mstp priority 8000 (this is 32768 in decimal) spanning-tree mstp msti 1 priority 8000 (this is 32768 in decimal) spanning-tree mstp msti 2 priority 8000 (this is 32768 in decimal) vlan create 100 type port msti 1 vlan create 200 type port msti 2 vlan members add 100 11,12 vlan members add 200 17,18
As a best practice we’ll enable edge-port (FastStart) and BPDU filtering on the remaining ports;
inter fa 1-10,13-16,19-48 spanning-tree mstp edge-port true spanning-tree bpdu-filtering enable
By default only legacy STP is enabled so we need to enable MSTP and reload the switch;
config t spanning-tree op-mode mstp copy config nvram boot -y
Once the switch has restarted we can continue the configuration. Let’s make all 4 ports 802.1q tagged ports;
config t vlan ports 11,12,17,18 tagging tagAll
Now we’ll create the MultiLink Trunk interfaces and add the port members. Just as we did with the ERS 5520 we’ll enable “mlt # bpdu all-ports”.
mlt 1 name "Primary Trunk Group" mlt 1 member 11,12 mlt 1 learning enable mlt 1 bpdu all-ports mlt 1 enable mlt 2 name "Secondary Trunk Group" mlt 2 member 11,12 mlt 2 learning enable mlt 2 bpdu all-ports mlt 2 enable
Now we’ll create the MSTI instances 1,2 along with VLANS 100,200 respectively;
spanning-tree mstp msti 1 spanning-tree mstp msti 1 enable spanning-tree mstp msti 2 spanning-tree mstp msti 2 enable spanning-tree mstp region region-name acme region-version 1 spanning-tree mstp priority f000 (this is 61440 in decimal) spanning-tree mstp msti 1 priority f000 (this is 61440 in decimal) spanning-tree mstp msti 2 priority f000 (this is 61440 in decimal) vlan create 100 type port msti 1 vlan create 200 type port msti 2 vlan members add 100 11,12 vlan members add 200 17,18
As a best practice we’ll enable edge-port (FastStart) and BPDU filtering on the remaining ports;
inter fa 1-10,13-16,19-24 spanning-tree mstp edge-port true spanning-tree bpdu-filtering enable
Let’s have a look at some of the show commands to see how things are running;
5520-48T-PWR#show autotopology nmm-table LSlot RSlot LPort IP Addr Seg ID MAC Addr Chassis Type BT LS CS RPort ----- --------------- -------- ------------ ---------------- -- --- ---- ----- 0/ 0 192.168.1.24 0x000000 001F0ACEBC01 5520-48T-PWR 12 Yes HTBT NA 1/11 192.168.1.23 0x00010b 000FCDF59601 460-24T-PWR 12 Yes HTBT 1/11 1/12 192.168.1.23 0x00010c 000FCDF59601 460-24T-PWR 12 Yes HTBT 1/12 460-24T-PWR#show autotopology nmm-table LSlot RSlot LPort IP Addr Seg ID MAC Addr Chassis Type BT LS CS RPort ----- --------------- -------- ------------ ---------------- -- --- ---- ----- 0/ 0 192.168.1.23 0x000000 000FCDF59601 460-24T-PWR 12 Yes HTBT NA 1/11 192.168.1.24 0x00010b 001F0ACEBC01 5520-48T-PWR 12 Yes HTBT 1/11 1/12 192.168.1.24 0x00010c 001F0ACEBC01 5520-48T-PWR 12 Yes HTBT 1/12
We can see that the SONMP table is exchanging packets across MLT 1 (11,12). That would lead me to guess that ports 17,18 are in discarding (blocking) mode. Let’s see if that’s the case;
5520-48T-PWR#show spanning-tree mstp port role 11,12,17,18 Port Role State STP Status Oper Status ---- ---------- ---------- ---------- ----------- 11 Designated Forwarding Enabled Enabled 12 Designated Forwarding Enabled Enabled 17 Designated Forwarding Enabled Enabled 18 Designated Forwarding Enabled Enabled 460-24T-PWR#show spanning-tree mstp port role 11,12,17,18 Port Role State STP Status Oper Status ---- ---------- ---------- ---------- ----------- 11 Root Forwarding Enabled Enabled 12 Root Forwarding Enabled Enabled 17 Alternate Discarding Enabled Enabled 18 Alternate Discarding Enabled Enabled
From the output above we can determine that the Ethernet Routing Switch 5520 is the root bridge and that MLT 2 (17,18) is an alternate path that’s currently discarding traffic on the Ethernet Switch 460. Lets confirm who’s the root bridge;
5520-48T-PWR#show spanning-tree mstp status Bridge Address: 00:1F:0A:CE:BC:00 Cist Root: 80:00:00:1F:0A:CE:BC:00 Cist Regional Root: 80:00:00:1F:0A:CE:BC:00 Cist Root Port: 0 Cist Root Cost: 0 Cist Regional Root Cost: 0 Cist Max Age: 20 seconds Cist Forward Delay: 15 seconds 460-24T-PWR#show spanning-tree mstp status Bridge Address: 00:0F:CD:F5:96:00 Cist Root: 80:00:00:1F:0A:CE:BC:00 Cist Regional Root: 80:00:00:1F:0A:CE:BC:00 Cist Root Port: MLT 1 Cist Root Cost: 0 Cist Regional Root Cost: 100000 Cist Max Age: 20 seconds Cist Forward Delay: 15 seconds
The root bridge is definitely the ERS 5520 as it should be since we set the bridge priority in our configuration above.
Hopefully you’ll agree that was pretty easy. You could of course set path costs/priorities so that you can administratively choose which path is the designated and alternate and for which MST instance. In a future post I will demonstrate how you can connect a Cisco Catalyst 3750-E to an Avaya switch while supporting MSTP.
Cheers!
References;
Avaya Ethernet Routing Switch RSTP/MSTP Technical Configuration Guide
In the two previous posts I covered how to create multiple VLANs, trunk those VLANs between multiple stackable Avaya Ethernet Routing Switches utilizing Multi-Link Trunking and how to create Layer 3 IP interfaces to be used for routing IP packets between those VLANs.
In this post I thought I would expand the network topology of my previous two posts to include a Cisco Catalyst 3750-E. I’ll specifically cover how to trunk (bridge) multiple VLANs between a stackable Avaya Ethernet Routing Switch and the Cisco Catalyst 3750-E and how to configure multiple interfaces in a Link Aggregation Group (LAG) utilizing LACP similar to Avaya’s proprietary MLT feature.
enable config t
Let’s start by making ports 45 and 46 trunk ports which will utilize 802.1Q tagging;
vlan ports 45,46 tagging tagAll
Let’s add the VLANs we wish to bridge across the trunk ports;
vlan members add 1 45,46 vlan members add 100 45,46 vlan members add 200 45,46
Now we’ll enable LACP on ports 45 and 46 using the same LACP key which will automatically create the LAG;
interface fastEthernet 45 lacp key 10 lacp mode active lacp timeout-time short lacp aggregation enable exit interface fastEthernet 46 lacp key 10 lacp mode active lacp timeout-time short lacp aggregation enable exit
4548GT-PWR#show lacp port 45,46 Admin Oper Trunk Partner Port Priority Lacp A/I Timeout Key Key AggrId Id Port Status ---- -------- ------- --- ------- ----- ----- ------ ----- ------- ------ 45 32768 Active A Short 10 12298 8224 32 302 Active 46 32768 Active A Short 10 12298 8224 32 303 Active 4548GT-PWR#show mac-address-table Mac Address Table Aging Time: 300 Number of addresses: 26 MAC Address Vid Source MAC Address Vid Source ----------------- ---- ------- ----------------- ---- ------- 00-02-B3-CB-77-A2 1 Port:19 00-04-61-9E-46-7E 1 Port:21 00-0C-29-64-33-F9 1 Port:19 00-0C-29-A5-CB-54 1 Port:19 00-0F-20-95-38-D5 1 Port:11 00-18-01-EA-F4-45 1 Port: 1 00-1C-11-6B-DC-6B 1 Port: 1 00-1C-11-6D-15-27 1 Port: 1 00-1C-11-6D-15-DC 1 Port: 1 00-1E-7E-7C-2C-00 1 00-1E-7E-7C-2C-40 1 00-1F-0A-CE-BC-01 1 Trunk:1 00-1F-0A-CE-BC-40 1 Trunk:1 00-1F-D0-D0-BE-2D 1 Port:17 00-23-EE-96-AA-21 1 Port: 1 00-24-B5-F6-94-02 1 Trunk:1 00-64-40-CF-4D-AD 1 Trunk:32 00-64-40-CF-4D-AE 1 Trunk:32 00-64-40-CF-4D-C0 1 Trunk:32 00-0A-E4-76-9C-C8 2 Port:44 00-24-DC-DF-0D-08 2 Port:43 00-A0-F8-5E-CE-BC 2 Port:39 00-1F-0A-CE-BC-41 100 Trunk:1 00-24-7F-99-84-70 100 Port:25 00-64-40-CF-4D-AD 100 Trunk:32 00-1E-CA-F3-1D-B4 200 Port:26 00-1F-0A-CE-BC-43 200 Trunk:1 00-64-40-CF-4D-AD 200 Trunk:32 4548GT-PWR#show mlt Id Name Members Bpdu Mode Status Type -- ---------------- ---------------------- ------ -------------- ------- ------ 1 MLT_to_ERS5520 47-48 All Basic Enabled Trunk 2 Trunk #2 NONE All Basic Disabled 3 Trunk #3 NONE All Basic Disabled 4 Trunk #4 NONE All Basic Disabled 5 Trunk #5 NONE All Basic Disabled 6 Trunk #6 NONE All Basic Disabled 7 Trunk #7 NONE All Basic Disabled 8 Trunk #8 NONE All Basic Disabled 9 Trunk #9 NONE All Basic Disabled 10 Trunk #10 NONE All Basic Disabled 11 Trunk #11 NONE All Basic Disabled 12 Trunk #12 NONE All Basic Disabled 13 Trunk #13 NONE All Basic Disabled 14 Trunk #14 NONE All Basic Disabled 15 Trunk #15 NONE All Basic Disabled 16 Trunk #16 NONE All Basic Disabled 17 Trunk #17 NONE All Basic Disabled 18 Trunk #18 NONE All Basic Disabled 19 Trunk #19 NONE All Basic Disabled 20 Trunk #20 NONE All Basic Disabled 21 Trunk #21 NONE All Basic Disabled 22 Trunk #22 NONE All Basic Disabled 23 Trunk #23 NONE All Basic Disabled 24 Trunk #24 NONE All Basic Disabled 25 Trunk #25 NONE All Basic Disabled 26 Trunk #26 NONE All Basic Disabled 27 Trunk #27 NONE All Basic Disabled 28 Trunk #28 NONE All Basic Disabled 29 Trunk #29 NONE All Basic Disabled 30 Trunk #30 NONE All Basic Disabled 31 Trunk #31 NONE All Basic Disabled 32 Trunk #32 45-46 Single DynLag/Basic Enabled Trunk
You might be looking at the output above and asking yourself what’s “Trunk 32”? Let me provide some quick background. You can have a total of 32 MLT/LAG trunks on a stackable Avaya Ethernet Routing Switch. When you create LACP trunks the switch automatically creates a LAG in the MLT table dynamically from the bottom up. While in the previous post I created “Trunk 1” by trunking ports 47 and 48 together (see above), in this post I’ve created an LACP trunk on ports 45 and 46 which will be reported it the switch as “Trunk 32”. You can also see it in the MAC/FDB table above.
enable config t
Let’s give the switch an IP address in VLAN 1 for management;
vlan 1 ip address 192.168.1.25 255.255.255.0 no shut exit
Let’s create VLAN 100 and VLAN 200 on the switch;
vlan 100 name "192-168-100-0/24" exit vlan 200 name "192-168-200-0/24" exit
Let’s add the appropriate edge ports to each VLAN;
interface range gigabitEthernet 1/0/1-12 switchport access vlan 1 exit interface range gigabitEthernet 1/0/13-24 switchport access vlan 100 exit interface range gigabitEthernet 1/0/25-36 switchport access vlan 200 exit
Let’s configure ports 45 and 46 as trunk ports and bond them together in channel-group utilizing LACP;
interface gigabitEthernet 1/0/45 switchport trunk encapsulation dot1q switchport mode trunk channel-protocol lacp channel-group 1 mode active interface gigabitEthernet 1/0/46 switchport trunk encapsulation dot1q switchport mode trunk channel-protocol lacp channel-group 1 mode active
SW-3750-E#show lacp neighbor
Flags: S - Device is requesting Slow LACPDUs
F - Device is requesting Fast LACPDUs
A - Device is in Active mode P - Device is in Passive mode
Channel group 1 neighbors
Partner's information:
LACP port Admin Oper Port Port
Port Flags Priority Dev ID Age key Key Number State
Gi1/0/45 FA 32768 001e.7e7c.2c00 16s 0x0 0x300A 0x2D 0x3F
Gi1/0/46 FA 32768 001e.7e7c.2c00 27s 0x0 0x300A 0x2E 0x3F
Switch#show mac address-table
Mac Address Table
-------------------------------------------
Vlan Mac Address Type Ports
---- ----------- -------- -----
All 0100.0ccc.cccc STATIC CPU
All 0100.0ccc.cccd STATIC CPU
All 0180.c200.0000 STATIC CPU
All 0180.c200.0001 STATIC CPU
All 0180.c200.0002 STATIC CPU
All 0180.c200.0003 STATIC CPU
All 0180.c200.0004 STATIC CPU
All 0180.c200.0005 STATIC CPU
All 0180.c200.0006 STATIC CPU
All 0180.c200.0007 STATIC CPU
All 0180.c200.0008 STATIC CPU
All 0180.c200.0009 STATIC CPU
All 0180.c200.000a STATIC CPU
All 0180.c200.000b STATIC CPU
All 0180.c200.000c STATIC CPU
All 0180.c200.000d STATIC CPU
All 0180.c200.000e STATIC CPU
All 0180.c200.000f STATIC CPU
All 0180.c200.0010 STATIC CPU
All ffff.ffff.ffff STATIC CPU
1 0004.619e.467e DYNAMIC Po1
1 000c.2964.33f9 DYNAMIC Po1
1 000c.29a5.cb54 DYNAMIC Po1
1 000f.2095.38d5 DYNAMIC Po1
1 0018.01ea.f445 DYNAMIC Po1
1 001c.116b.dc6b DYNAMIC Po1
1 001c.116d.1527 DYNAMIC Po1
1 001c.116d.15dc DYNAMIC Po1
1 001e.7e7c.2c01 DYNAMIC Po1
1 001e.7e7c.2c2d DYNAMIC Po1
1 001e.7e7c.2c2e DYNAMIC Po1
1 001f.d0d0.be2d DYNAMIC Po1
1 0023.ee96.aa21 DYNAMIC Po1
1 00a0.f85e.cebd DYNAMIC Po1
100 0024.7f99.84e9 DYNAMIC Po1
200 0008.02e4.890a DYNAMIC Gi1/0/25
200 001e.caf3.1db4 DYNAMIC Po1
Total Mac Addresses for this criterion: 37You might be asking why didn’t I assign the VLANs to the trunk ports on the Cisco Catalyst 3750-E… well with Cisco switches a trunk port is by default a member of all the VLANs that exist on the switch. So you don’t need to specifically add a VLAN to a trunk port, however, you can override the default behavior by telling the switch to only carry specific VLANs on a specific trunk port – this is called VLAN pruning.
Please feel free to point out any inconsistencies or errors I might have made.
Cheers!