Michael McNamara
technology, networking and IP telephony
802.1Q VLAN Tagging on a Cisco Catalyst 3750-E
14January 29, 2011
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.
Avaya Ethernet Routing Switch 4548
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
Avaya Ethernet Routing Switch 4548 – Show Commands
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.
Cisco Catalyst 3750-E
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 1/0/24-36 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
Cisco Catalyst 3750-E – Show Commands
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!
802.1Q VLAN Tagging on an Ethernet Routing Switch
14January 27, 2011
In my previous post I laid out the basics of how to configure multiple VLANs and enable IP routing on a stackable Avaya Ethernet Routing Switch. In this post I’m going to expand that topic to include trunking (802.1q) those VLANs to a second Ethernet Routing Switch. In this example I’ll add an Ethernet Routing Switch 4548 to the Ethernet Routing Switch 5520 that I had previously configured and deployed. We’ll create a Multi-Link Trunk between the two switches to bridge multiple VLANs across the 802.1q compliant link. Here’s a diagram of what the network should look like when we’re done;
In order to test I’ll move two of the IP phones to the Ethernet Routing Switch 4548 and I’ll use an old laptop to help verify the bridging.
Ethernet Routing Switch 4548
Let’s start with the Ethernet Routing Switch 4548GT-PWR and add the necessary configuration there first;
enable config t
We start by creating VLAN 100 and VLAN 200 on the Ethernet Routing Switch 4548;
vlan create 100 name "192-168-100-0/24" type port vlan members remove 1 25,27,29,31,33,35 vlan members add 100 25,27,29,31,33,35 vlan port 25,27,29,31,33,35 pvid 100 vlan create 200 name "192-168-200-0/24" type port vlan members remove 1 26,28,30,32,34,36 vlan members add 200 26,28,30,32,34,36 vlan port 26,28,30,32,34,36 pvid 200
I’m not going to create a Layer 3 IP interfaces on these VLANs since the Ethernet Routing Switch 5520 is already routing for us. We just want to bridge the frames between the two switches not route them (not in this post anyway). Now let’s configure the ports that will make up the Mulit-Link Trunk;
vlan port 47,48 tagging TagAll vlan members add 1 47,48 vlan members add 100 47,48 vlan members add 200 47,48 vlan port 47,48 pvid 1 mlt 1 disable mlt 1 name "MLT_to_ERS5520" mlt 1 learning disable mlt 1 member 47,48 mlt 1 enable
That’s pretty much it. We enabled tagging on the uplink/downlink ports, added the necessary VLANs to the ports and then created and enabled a MLT.
Ethernet Routing Switch 4548 – Show Configuration
That should be the configuration for the Ethernet Routing Switch 4548… let’s just have a quick look at the VLANs;
4548GT-PWR(config)#show vlan
Id Name Type Protocol User PID Active IVL/SVL Mgmt
--- -------------------- -------- ---------------- -------- ------ ------- ----
1 VLAN #1 Port None 0x0000 Yes IVL Yes
Port Members: 1-24,47-48
2 VLAN #2 Port None 0x0000 Yes IVL No
Port Members: 37-46
100 192-168-100-0/24 Port None 0x0000 Yes IVL No
Port Members: 25,27,29,31,33,35,47-48
200 192-168-200-0/24 Port None 0x0000 Yes IVL No
Port Members: 26,28,30,32,34,36,47-48
Total VLANs: 4Let’s just check the Multi-Link Trunk configuration… if that’s wrong we could end up with a loop in the network;
4548GT-PWR(config)#show mlt 1 Id Name Members Bpdu Mode Status -- -------------------- ---------------------- ------ -------------- ------- 1 MLT_to_ERS5520 47-48 All Basic Enabled
You can see from the commands above that the ports are configured with the appropriate VLANs and the MLT is enabled.
Ethernet Routing Switch 5520
Let’s add the necessary configuration to the Ethernet Routing Switch 5520-PWR. I’m not going to repeat all the commands I performed in the yesterday’s post, instead I’ll just build upon the previous configuration adding what we need for the 802.1q trunking and the Multi-Link Trunking;
enable config t
vlan port 47,48 tagging TagAll vlan members add 1 47,48 vlan members add 100 47,48 vlan members add 200 47,48 vlan port 47,48 pvid 1 mlt 1 disable mlt 1 name "MLT_to_ERS4548" mlt 1 learning disable mlt 1 member 47,48 mlt 1 enable
Ethernet Routing Switch 5520 – Show Configuration
That should be the configuration for the Ethernet Routing Switch 5520… let’s just have a quick look at the VLANs;
5520-48T-PWR#show vlan
Id Name Type Protocol PID Active IVL/SVL Mgmt
--- -------------------- -------- ---------------- -------- ------ ------- ----
1 test Port None 0x0000 Yes IVL Yes
Port Members: 1-12,37-48
100 192-168-100-0/24 Port None 0x0000 Yes IVL No
Port Members: 13-24,47-48
101 10-101-20-0/24 Port None 0x0000 Yes IVL No
Port Members: 25-36
200 192-168-200-0/24 Port None 0x0000 Yes IVL No
Port Members: 47-48
Total VLANs: 4Let’s just check the Multi-Link Trunk configuration… if that’s wrong we could end up with a loop in the network;
5520-48T-PWR#show mlt 1 Id Name Members Bpdu Mode Status Type -- ---------------- ---------------------- ------ -------------- ------- ------ 1 MLT_to_ERS4548 47-48 All Basic Enabled Trunk
Since all stackable Avaya Ethernet Routing Switches support Auto-MDIX I can just use two regular CAT5e patch cables to connect the switches together. If the switches didn’t support Auto-MDIX I would need to use two crossover cables between them.
Ethernet Routing Switch 4548 – Operational Status
With link up on ports 47 and 48 I can check the following information. The topology table will show me the physical connections between the two switches. The MAC/FDB table will show me that there are multiple MAC/FDB entries in VLANs 100 and 200 being learned across “Trunk 1″. The LLDP table will show me the Avaya IP phones that I’ve connected to ports 25 and 26.
4548GT-PWR#show autotopology nmm-table
LSlot RSlot
LPort IP Addr Seg ID MAC Addr Chassis Type BT LS CS RPort
----- --------------- -------- ------------ ---------------- -- --- ---- -----
0/ 0 192.168.1.25 0x000000 001E7E7C2C01 4548GT-PWR 12 Yes HTBT NA
1/47 192.168.1.50 0x000130 001F0ACEBC01 5520-48T-PWR 12 Yes HTBT 1/48
1/48 192.168.1.50 0x00012f 001F0ACEBC01 5520-48T-PWR 12 Yes HTBT 1/47
4548GT-PWR#show mac-address-table
Mac Address Table Aging Time: 300
Number of addresses: 20
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
00-18-01-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-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
00-0A-E4-76-9C-C8 2 Port:45 00-1F-0A-CE-BC-01 2 Trunk:1
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
00-24-7F-99-84-E9 100 Trunk:1 00-1E-CA-F3-1D-B4 200 Port:26
4548GT-PWR#show lldp neighbor
-------------------------------------------------------------------------------
lldp neighbor
-------------------------------------------------------------------------------
Port: 26 Index: 4 Time: 13 days, 22:42:31
ChassisId: Network address IPv4 192.168.200.5
PortId: MAC address 00:1e:ca:f3:1d:b4
SysCap: TB / TB (Supported/Enabled)
PortDesc: Avaya IP Phone
SysDescr: Avaya IP Telephone 1120E, Firmware:SIP1120e04.00.04.00
-------------------------------------------------------------------------------
Port: 25 Index: 6 Time: 13 days, 22:43:48
ChassisId: Network address IPv4 192.168.100.98
PortId: MAC address 00:24:7f:99:84:70
SysCap: TB / TB (Supported/Enabled)
PortDesc: Avaya IP Phone
SysDescr: Avaya IP Telephone 1220, Firmware:SIP12x004.00.04.00
-------------------------------------------------------------------------------
Sys capability: O-Other; R-Repeater; B-Bridge; W-WLAN accesspoint; r-Router;
T-Telephone; D-DOCSIS cable device; S-Station only.
Total neighbors: 2Ethernet Routing Switch 5520 – Operational Status
I can check all the same information on the ERS5520.. The topology table will show me the physical connections between the two switches. The MAC/FDB table will show me that there are multiple MAC/FDB entries in VLANs 100 and 200 being learned across “Trunk 1″. The LLDP table will show me the Avaya IP phones that I’ve connected to ports 13 and 25.
5520-48T-PWR#show autotopology nmm-table
LSlot RSlot
LPort IP Addr Seg ID MAC Addr Chassis Type BT LS CS RPort
----- --------------- -------- ------------ ---------------- -- --- ---- -----
0/ 0 192.168.1.50 0x000000 001F0ACEBC01 5520-48T-PWR 12 Yes TPCH NA
1/47 192.168.1.25 0x00012f 001E7E7C2C01 4548GT-PWR 12 Yes TPCH 1/47
1/48 192.168.1.25 0x000130 001E7E7C2C01 4548GT-PWR 12 Yes TPCH 1/48
5520-48T-PWR#show mac-address-table
Mac Address Table Aging Time: 300
Number of addresses: 16
MAC Address Vid Source MAC Address Vid Source
----------------- ---- ------- ----------------- ---- -------
00-02-B3-CB-77-A2 1 Trunk:1 00-04-61-9E-46-7E 1 Trunk:1
00-0C-29-64-33-F9 1 Trunk:1 00-0C-29-A5-CB-54 1 Trunk:1
00-18-01-EA-F4-45 1 Trunk:1 00-1C-11-6B-DC-6B 1 Trunk:1
00-1C-11-6D-15-27 1 Trunk:1 00-1C-11-6D-15-DC 1 Trunk:1
00-1E-7E-7C-2C-01 1 Trunk:1 00-1E-7E-7C-2C-40 1 Trunk:1
00-1F-0A-CE-BC-00 1 00-1F-0A-CE-BC-40 1
00-1F-D0-D0-BE-2D 1 Trunk:1 00-23-EE-96-AA-21 1 Trunk:1
00-24-B5-F6-94-02 1 Port: 9 00-1F-0A-CE-BC-41 100
00-24-7F-99-84-70 100 Trunk:1 00-24-7F-99-84-E9 100 Port:15
00-1E-CA-F3-1D-B4 200 Trunk:1
5520-48T-PWR#show lldp neighbor
-------------------------------------------------------------------------------
lldp neighbor
-------------------------------------------------------------------------------
Port: 13 Index: 5 Time: 0 days, 00:02:00
ChassisId: Network address IPv4 192.168.100.4
PortId: MAC address 00:24:b5:f6:94:02
SysCap: TB / TB (Supported/Enabled)
PortDesc: Avaya IP Phone
SysDescr: Avaya IP Telephone 1165E, Firmware:SIP1165e04.00.04.00
-------------------------------------------------------------------------------
Port: 25 Index: 6 Time: 0 days, 00:02:19
ChassisId: Network address IPv4 192.168.200.99
PortId: MAC address 00:24:7f:99:84:e9
SysCap: TB / TB (Supported/Enabled)
PortDesc: Avaya IP Phone
SysDescr: Avaya IP Telephone 1220, Firmware:SIP12x004.00.04.00
-------------------------------------------------------------------------------
Sys capability: O-Other; R-Repeater; B-Bridge; W-WLAN accesspoint; r-Router;
T-Telephone; D-DOCSIS cable device; S-Station only.
Total neighbors: 2Would you be interested in seeing a screencast of this whole process?
Let me know if you have any questions or would like to point out corrections!
Cheers!
VLANs and IP Routing on an Ethernet Routing Switch
12January 26, 2011
I’ve had a number of discussions recently with people asking how to configure VLANs and IP routing on the stackable Avaya Ethernet Routing Switches. I thought I would take a step back and document some basic configurations for those that might still have questions or for anyone that might be looking for some example configurations. In this post I specifically focus on how to configure multiple VLANs with IP routing on a single Ethernet Routing Switch 5520. (In a future post I’ll examine how to tag VLANs between multiple switches.) The example configuration below should be applicable to any model of the Ethernet Routing Switch 4500 or Ethernet Routing Switch 5000 series switches. This example configuration matches a build I recently setup to test the compatibility of the Avaya 1100 and 1200 series IP phones to connect to an Asterisk IP PBX. You can review a diagram of the test network in the figure to the right.
We have a single Ethernet Routing Switch 5520 (running software 6.2) with 3 separate VLANs each with their own Layer 3 IP interface. We’ll enable IP routing, configure DHCP forwarding (relay) and apply some basic best practices. The CentOS Linux sever at 192.168.1.6 will server multiple rolls; SIP server, DHCP server and TFTP server. In this example I’ll assume that the switch has a factory default configuration.
Let’s get started by entering configuration mode;
enable config terminal
The “Default VLAN” already exists in the factory configuration so let’s rename it and assign an IP address to the Layer 3 IP interface;
vlan name 1 "192-168-1-0/24" interface vlan 1 ip address 192.168.1.50 255.255.255.0 1 exit
Let’s create VLAN 100, assign ports 13-24 to that VLAN, set the PVID for each port to VLAN 100, create a Layer 3 IP interface and enable DHCP relay;
vlan create 100 name "192-168-100-0/24" type port vlan members remove 1 13-24 vlan members add 100 13-24 vlan port 13-24 pvid 100 interface vlan 100 ip address 192.168.100.1 255.255.255.0 2 ip dhcp-relay exit ip dhcp-relay fwd-path 192.168.100.1 192.168.1.6 enable
Let’s create VLAN 200, assign ports 25-36 to that VLAN, set the PVID for each port to VLAN 100, create a Layer 3 IP interface and enable DHCP relay;
vlan create 200 name "192-168-200-0/24" type port vlan members remove 1 25-36 vlan members add 200 25-36 vlan port 25-36 pvid 200 interface vlan 200 ip address 192.168.200.1 255.255.255.0 3 ip dhcp-relay exit ip dhcp-relay fwd-path 192.168.200.1 192.168.1.6 enable
Let’s make sure that IP routing is enabled globally;
ip routing
There’s no need to add any additional IP static routes since this is a closed network. However, if there was an Internet router at 192.168.1.1 we would use the following command to create a default route to 192.168.1.1;
ip route 0.0.0.0 0.0.0.0 192.168.1.1 1
Whenever you remove a port from all VLANs it get’s removed from the Spanning Tree Group so it’s always a good idea to re-apply Spanning Tree to every port and set it to Fast learning. It’s also usually a very good idea to enable broadcast and Multicast rate-limiting (this is done in the hardware ASIC), setting it to 10% of the maximum port utilization;
interface fastEthenet All spanning-tree learning fast rate-limit both 10 exit
Cheers!
