Lucent Technologies Cajun P220 Instruction Manual

Release Notes Supporting
Cajun P220, P550, and P550R Switches
Software Release 4.0.1
November 1999
Part # 610-0120-061

Release 4.0.1 Notes Supporting the Cajun P220, Cajun P550, and Cajun P550R Switches
© Copyright LUCENT TECHNOLOGIES 1999 ALL RIGHTS RESERVED
Printed in USA, November 1999
The products, specifications, and other technical information regarding the products contained in this document are subject to
change without notice. All information in this document is believed to be accurate and reliable, but is presented without warranty
of any kind, express or implied, and users must take full responsibility for their application of any products specified in this
document. Lucent disclaims responsibility for errors which may appear in this document, and it reserves the right, in its sole
discretion and without notice, to make substitutions and modifications in the products and practices described in this document.
Lucent, Cajun, CajunDocs, OpenTrunk, P550, P220 and CajunView are trademarks of Lucent Technologies.
Microsoft, Windows, Windows NT, Windows 95, Windows 98, and Internet Explorer are trademarks or registered trademarks of
Microsoft Corporation in the U.S. and/or other countries.
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other countries.
3Com is a registered trademark and PACE is a trademark of 3Com or its subsidiaries.
Adobe is a registered trademark of Adobe Systems Incorporated.
Bay Networks and System 5000 are registered trademarks of Nortel Networks.
Cisco Catalyst 5000 is a registered trademark of Cisco Systems Incorporated.
ALL OTHER TRADEMARKS MENTIONED IN THIS DOCUMENT ARE PROPERTY OF THEIR RESPECTIVE OWNERS.

Cajun P220, P550, P550R Switch Release Notes, Release 4.0.1 3
Chapter 1 Read Me First
This section of the Release Notes Supporting the Cajun P220 and Cajun P550 family of switches
contains information that is crucial to know before proceeding to install or use the Cajun switch.
Please review the following release notes before continuing to the Overview section.
CAUTION: Release 4.0.1 embedded software requires a MINIMUM of 16 MB DRAM
(Dynamic Random Access Memory) to run on a Cajun P550 Layer 2
supervisor module. BEFORE upgrading, ensure that the switch meets this
16 MB DRAM requirement. A memory upgrade is not required for a Cajun
P550 Layer 3 supervisor module, or the Cajun P220.
CAUTION: Release 4.0.1 introduces a new ASCII configuration file format that replaces
the traditional binary (*.cfg) files used to store and restore saved
configurations. You must save your binary configuration before upgrading the
switch to Release 4.0.1 or rebooting the switch for the first time using Release
4.0.1. For information about saving your binary configuration, refer to the
“Installation” section of these release notes.
CAUTION: When making configuration changes to the switch, explicitly save changes by
copying the running configuration to the startup configuration to ensure that
the changes persist after the switch is restarted.

Cajun P220, P550, P550R Switch Release Notes, Release 4.0.1 4
Chapter 2 Overview
This set of release notes supports the Cajun P220, Cajun P550, and Cajun P550R switches. For
detailed information about your product, refer the basic set of user documentation. These release
notes are intended to get you up and running as quickly as possible. The following topics are
covered:
•Read Me First
•Overview
•New Features
•Product Binaries
•Installation
•Problems and Workarounds
•Functional Restrictions
•Bug Fixes
•Additional Undocumented Commands

Cajun P220, P550, P550R Switch Release Notes, Release 4.0.1 5
Chapter 3 New Features
This section covers features specified for Release 4.0.1 of the Cajun P220, Cajun P550, and Cajun
P550R switches. All supporting documentation is available from the Lucent Technologies Web
site at HTTP://pubs.lucentctc.com.
The Cajun P550R switch, which supports Layer 3 technology, contains features that are not
available in the Layer 2 Releases of the switch.
The following new features are available in Release 4.0.1 through the Enhanced Command Line
Interface or the Web Agent:
•VTP eavesdropping (Cisco compatibility)
•LDAP Release 3 client necessary for RealNet Rules support
•Support for the following MIBs:
-Policy capabilities MIB (proprietary)
-RIP v1/v2 (RFC1724)
-OSPFv2 (RFC1850)
-IGMP – Internet Group Management Protocol MIB (draft-ietf-edmr-igmp-mib-
12.txt)
-IP Interface (proprietary)
-IP Forwarding/Route Table (RFC2096)
-IP ARP (RFC2011)
-DVMRP (draft)
-AppleTalk (RFC1243)
-IP Access List (proprietary)
-IPX Interfaces (proprietary)
•VRRP (Virtual Redundant Router Protocol, RFC 2338)
•Multiple configuration images – Multiple configuration files may be stored in NVRAM
and loaded into the switch at a later date

Cajun P220, P550, P550R Switch Release Notes, Release 4.0.1 6
•IPX Multinetting
•ASCII text configuration files with upload/download
•Redundant backplane support for Cajun P550R switches
•SNTP (Simple Network Time Protocol)
•AppleTalk Routing
•Hexadecimal addressing – subnet masks may be represented by a hexadecimal value
•Access lists
-Source and destination IP address wildcarding and TCP/UDP ranges
-TCP established connection filtering
•Configuration scripting via command line execution
Additional Undocumented Features
Features in this section are not documented in the released product documentation.
BOOTP/DHCP Relay Gateway
You can Enable or Disable the BOOTP/DHCP Relay Gateway from the Enhanced CLI in Interface
mode using the command '[no] ip bootp-dhcp gateway'. From the Cajun Switch Web
Agent, this setting is located in the IP Interfaces dialog box. To open the IP Interfaces dialog box,
in the IP Configuration section of the Web Agent, click Interfaces. The default for this parameter
is Disable.
This parameter affects how the router chooses a source interface for the reception of BOOTP/
DHCP requests received on a VLAN, as this source interface determines the value that is inserted
by the router into the giaddr field and designates the IP subnet pool that the DHCP server uses
to assign an address.

Cajun P220, P550, P550R Switch Release Notes, Release 4.0.1 7
The source interface is determined as follows:
Table 1-1: Source Interface Determination: BOOTP/DHCP Relay Gateway
Number of
Interfaces on
VLAN
Number of Interfaces
with Parameter
Enabled Source Interface
1N/A The interface itself.
10The first UP interface found.
11Preferred interface if UP; otherwise, first
UP interface found.
11First preferred UP interface found;
otherwise, first UP interface found.

Cajun P220, P550, P550R Switch Release Notes, Release 4.0.1 8
Chapter 4 Product Binaries
The following table shows the binary files that contain embedded software for the Release 4.0.1
Cajun P220, Cajun P550, and Cajun P550R switches.
Table 1-2: Product Binary Files
Type of Switch Binary File
Cajun P220 m2200_v4.0.1.bin
Cajun P550 m5500_v4.0.1.bin
Cajun P550R m5500r_v4.0.1.bin

Cajun P220, P550, P550R Switch Release Notes, Release 4.0.1 9
Chapter 5 Installation
CAUTION: Release 4.0.1 embedded software requires a MINIMUM of 16 MB DRAM
(Dynamic Random Access Memory) to run on a Cajun P550 Layer 2
supervisor module. BEFORE upgrading, ensure that the switch meets this
16 MB DRAM requirement. A memory upgrade is not required for a Cajun
P550 Layer 3 supervisor module, or the Cajun P220.
NOTE: Release 4.0.1 introduces a new ASCII configuration file format that replaces the
traditional binary (*.cfg) files used to store and restore saved configurations. Before
upgrading the switch to Release 4.0.1, review the Installation section of these release
notes.
The following memory upgrade kits are available through your local sales representative:
Use the following procedure to upgrade from Release 3.1 to Release 4.0.1 of the Cajun P220,
Cajun P550, or Cajun P550R switch. For more detailed installation procedures, refer to the Cajun
P550/P220 Switch Installation Guide.
Downgrading to a Previous Release
1. In the CLI Configuration section of the Web Agent, click Config File Management.
In the Configuration File Management dialog box, save your Release 4.0.1 Running
Configuration (running.txt) to a TFTP server for potential later use.
2. From the Release 4.0.1 Enhanced CLI, clean the current configuration by issuing the
nvram init command.
3. Configure the switch to select the APP that contains the previous code release.
4. Reset the switch.
Table 1-3: Module Descriptions
Description Model Number
16 MB Memory
Upgrade Kit M5500-MEM16
32 MB Memory
Upgrade Kit M5500-MEM32

Cajun P220, P550, P550R Switch Release Notes, Release 4.0.1 10
5. Use the CLI setup command to configure the switch.
6. Restore the binary configuration files of the release (3.1 or previous) you want to
restore. These configuration files do not reflect any changes you made to the
running configuration while using Release 4.0.1.
Problem: Release 4.0.1 of the Cajun switch contains new range-checking procedures
that may be reasonably more restrictive than those of previous releases.
Workaround: If you have a parameter in 3.1 that is outside the 4.0 range, it will be
noted in the Script Log File. After the second reboot the switch, check the Script Log File
to find out if any errors occurred as the script executed. To check the Script Log File, click
Script Log File in the CLI Configuration section of the Web Agent. If errors were
found, scroll up to find the particular error message. If you prefer to use the Enhanced
CLI, at the system prompt, type: show file logfile.txt.
NOTES:
•Some of the associated CLI command incorrectly list “Multilayer” and “3Com”.
These are not supported by the Cajun P550 48-Port 10/100 Media Module (M5548E-
100TC).
•In Release 4.0.1 of the Cajun switch, the Web Agent provides a new set of dialog
boxes in which you can:
-View startup and running configuration files
-View script execution log files
-Copy and manage configuration files
Ensure that you copy configuration files to a TFTP server or other storage location using
the Configuration File Management dialog box.
Upgrading from Release 3.1 or Previous Releases
Use the following procedure to upgrade the switch from Release 3.1 to Release 4.0.1.
NOTE: The Cajun switch does not support a direct upgrade to Release 4.0.1 from
releases prior to Release 3.0. If your switch runs a release prior to 3.0, upgrade the
switch to Release 3.0 or 3.1. Then, use the following procedure to upgrade the switch
from Release 3.0 or 3.1 to Release 4.0.1.

Cajun P220, P550, P550R Switch Release Notes, Release 4.0.1 11
7. Save your Release 3.1 binary configuration file:
a. In the Memory Subsystems section of the Web Agent, click TFTP Update.
b. In the TFTP Server IP Address field, enter the IP address of the TFTP server to
which you will upload the 3.1 binary configuration file.
c. In the Filename field, specify the destination path and filename of the
configuration file. This is the TFTP server path.
d. In the TFTP Target Section pull-down menu, select Save Configuration
(binary).
e. Click the Update button.
f. Click the Status button. View the Transfer Completed message in the System
Status frame of the TFTP Update dialog box.
8. In the Memory Subsystems section of the Web Agent, click TFTP Update. In the
TFTP Update dialog box, download V4.0 onto your switch (into either APP1 or APP2).
9. Configure the switch to choose the appropriate APP (that contains V4.0 code) at the
next reboot.
10. Reset the switch to load the V4.0 image.
11. Refresh your Web browser window.
12. Verify the existence of the startup.txt file in NVRAM: in the CLI Configuration
section of the Web Agent, click Startup Config.
NOTE: The script log file (a new feature of Release 4.0.1) records the output of scripts
executed on the system, including the startup.txt file. Upon initial upgrade to Release
4.0.1, the script is generated but not run, and output is not initially recorded in the file.
13. In the CLI Configuration section of the Web Agent, click Script Log File. Scroll to
the bottom of the Script Log File to find out if any errors occurred as the script
executed. If errors were found, scroll up to find the particular error message.

Cajun P220, P550, P550R Switch Release Notes, Release 4.0.1 12
Chapter 6 Problems and Workarounds
The following problems and workarounds generally apply to all Cajun switches unless expressly
specified.
Cajun 48-Port 10/100 Media Module
Problem: Due to the positioning of the Cajun P550 48-Port Media Module (M5548E-
100TC) as a high-density desktop connectivity module, the following functionality is not
supported:
•Multi-layer and 3Com trunk mode
•Link aggregation (hunt groups)
•Port mirroring
•3Com mapping table selection
•Flow control setting of "Enable with Aggressive Backoff"
•PACE priority mode
•Spanning tree mode (disabled by factory default; enabled in other cases)
•Port statistics: intra-BCM5308 unicast frames not reflected
Additionally, flow control and rate limiting available only on a per-module basis
Workarounds:
•If link aggregation is required over a 10/100TX Link, use a Cajun P550 20-port
Module (M5520-100TX) or a Cajun P550 Layer 3 12-port Copper Module (M5512R-
100TX).
•If a port is inadvertently configured to use Multilayer tagging, reconfigure the port to
use either Clear or IEEE 802.1Q tagging. To reconfigure the port from the Enhanced
CLI, enter the following command at the system prompt:
set port trunking-format {<mod-num>|<mod-port-range>}[...[,]{<mod-
num>|<mod-port-range>}] { clear | ieee-802.1Q}

Cajun P220, P550, P550R Switch Release Notes, Release 4.0.1 13
If a port is inadvertently configured to use 3Com tagging, use the following procedure:
1. Reconfigure the port to use either Clear or IEEE 802.1Q tagging.
2. Copy (Save) the Running-Config to the Startup-Config.
3. Reboot the switch.
NOTES:
•3Com VLT Tagging is not supported but can be enabled on the Cajun P550 48-port
Media Module’s (M5548E-100TC) internal switch ports by using the Web or CLI
management interface.
•The Cajun P550 48-port Media Module (M5548E-100TC) has been optimized for
desktop connections. Spanning Tree topology change convergence time can be
lengthy. This could lead to loss of connectivity and/or wrongful flow of data.
Command Line Interface
The command "set vlan <vlan-id> <port>" is used to bind additional ports to a VLAN if
trunking is enabled on that port. To set the port default VLAN for a port, use "set port vlan
{<mod-num>|<mod-port-range>}[...[,]{<mod-num>|<mod-port-range>}] <vlan-id>".
Cajun DocServer
NOTE: Release notes for the Cajun DocServer incorrectly excludes mention of the P550
platform. Both the Cajun P550 and P220 platforms are supported.
DVRMP
NOTE: The Cajun P550R Switch may lose a small number of DVMRP neighbor-to-
neighbor probe messages which may cause multicast routing instability under heavy
loads.

Cajun P220, P550, P550R Switch Release Notes, Release 4.0.1 14
Front Panel Display
Problem: The 'lastlink' application on the front panel display does not work on the
Cajun P220FE or P220G.
Workaround: Currently, no workaround is available.
Hardware
Frames Transmitted with CRC Errors
For the Cajun P550 20-port Module, Model M5520-100TX (P/N 311-0020-000: Revision Level
A or B), and the Cajun P550 12-port Module, Model M5512R-100TX, a temperature sensitivity
problem has been found when operating at 10Mbps. This sensitivity will result in the port
transmitting frames with CRC errors. These frames, since they have CRC errors, are then
dropped by the receiving station. Note that this problem only occurs at 10Mbps. 100Mbps
operation is not affected.
Software Release v1.0.17 (or later) has implemented a new configuration that disables the
power saving mode of the Phy chip. Disabling the power saving mode has the effect of moving
the operational temperature of the part past the problem range. Testing this software
configuration is 100% successful in resolving the error.
The software configuration command is only available from the CLI. It is saved in NVRAM.
Users should only disable the power saving mode for ports that are experiencing this problem.
Disabling the power saving mode for parts that are operating at a lower temperature than the
problem range may accidentally raise the temperature into the problem range. In legacy-cli
mode, use the following command to disable the power saving mode for ports:
Cajun> port set DisablePowerSave <slot>.<port> on
NOTE: To enter legacy mode, type legacy-cli at the command prompt. To return to
the Enhanced CLI from legacy mode, type exit at the command prompt.
Hot Swap Modules
Hot swapping modules may cause SEPROM and SMAC panic messages to appear in the event
log. These messages are for informational purposes only and should be ignored.

Cajun P220, P550, P550R Switch Release Notes, Release 4.0.1 15
Loopback Tests
Loopback tests on ports may fail when there is traffic present on the link at start-up.
M5520-TX Loopback Tests During Cold Start
Occasionally M5520-TX (P/N M5520-100TX) boards with a Quality Phy will fail loopback tests
when the board initially is started. The problem corrects itself as the board warms up.
M5520-TX Auto-negotiation with Xircom Adapter Cards
M5520-TX (P/N M5520-100TX) boards manufactured with a Quality Phy do not autonegotiate
with Xircom brand adapter cards. If you are having this problem, disable auto-negotiation on
the affected ports, and set the port speed and duplex state manually.
Oversized Packets
Oversized packets are not counted in itemized statistics if the packet size is between 1519 and
1548 bytes.
Short Cables May Cause Auto-negotiation Problems
You may experience difficulties with auto-negotiation between some releases of the 10/
100Base-TX Module (M5510-100FX, M5520-100TX, M5510R-100FX, M5512R-100TX) and
adapter cards using physical interfaces manufactured by National Semiconductor. The symptom
is loss of connectivity. You can address this problem by either disabling auto-negotiation, or
using a patch cable longer that 5 meters. Use the following Enhanced Command Line Interface
command in legacy mode to correct the situation:
Cajun> port set NationalPhyMode <slot>.<port> enable
NOTE: To enter legacy mode, type legacy-cli at the command prompt. To return to
the Enhanced CLI from legacy mode, type exit at the command prompt.
NOTE: The factory default for ports now sets the National Phy mode to enabled.

Cajun P220, P550, P550R Switch Release Notes, Release 4.0.1 16
Intelligent Multicasting
Problem: Intelligent Multicasting can block protocols to non-multicast routers. If you
have enabled Intelligent Multicasting and configured a VLAN attached to one or more
non-multicast routers or multicast-capable endstations, Intelligent Multicasting will
configure router ports where multicast-enabled routers reside. These multicast router
ports are necessary to allow all multicast packets to the adjacent multicast routers. Non-
multicast enabled routers will not be considered router ports, and will not receive
multicast traffic for which an Intelligent Multicast session was created. The problem can
arise when multiple IP multicast addresses map to the same multicast MAC address,
resulting in protocol packets not being sent to the adjacent non-multicast enabled
routers.
EXAMPLE:
The unicast routing protocol in use on all connected routers is OSPF, and all ports are on
the same VLAN. An endstation joins the IP multicast group 226.128.0.5 on port 1. The
MAC address for the group is 01:00:5E:00:00:05. IGMP snooping creates a session for
this MAC address, with port 1 as the client port. There is a non-multicast OSPF router
attached to port 2. OSPF uses the IP multicast link-scoped group 224.0.0.5, which also
maps to a MAC address of 01:00:5E:00:00:05. Because port 2 is not a router port, and it
is not part of the 01:00:5E:00:00:05 session, the switch will only pass OSPF messages out
port 1.
Other protocols, such as the Service Location Protocol (RFC 2608), use 224.0.1.22 and
224.0.1.35, which can be blocked by endstations joining sessions that map to the same
MAC address.
Workaround: Make certain that all ports connected to a router are configured as router
ports to ensure that all router-to-router messages will not be blocked. If other non-
router protocols such as the Server Location service are in use, create static sessions as
needed. Also, do not create static sessions that will conflict with the protocols in use on
your network. For a complete list of internet multicast addresses recognized by the
IANA, go to http://www.isi.edu/in-notes/iana/assignments/multicast-addresses.
NOTE: By default, the default “Rate Limiting” state for 10/100 Megabit ports is
Enabled, and multicast traffic is rate-limited (to 20%) on 10/100 Megabit ports. When
transmitted from these ports, multicast traffic is rate-limited unless Intelligent
Multicasting is enabled. If Intelligent Multicasting is enabled, the multicast traffic for
which the Intelligent Multicast session was created will not be subject to rate limiting
unless the rate limiting state is set to Enabled (all multicast included). If you do not
want to enable rate limiting of multicast traffic on a port, either 1)Enable Intelligent
Multicasting, or 2) Disable Rate-limiting on the port.

Cajun P220, P550, P550R Switch Release Notes, Release 4.0.1 17
OSPF
Problem: Upgrading the switch from a Release 3.1 or other previous release to Release
4.0.1 may cause the loss of your virtual link configuration.
Workaround: After upgrading and resetting the switch, view your running
configuration to ensure that virtual links are intact. (To view your running
configuration, click Running Config in the CLI Configuration section of the Web
Agent.) If the virtual link configuration is lost, reconfigure the virtual links.
NOTES:
•When the Cajun P550 first boots up as an ABR or ASBR, it may send an ASBR
advertisement for itself. This advertisement is later flushed by the system.
•When changing the OSPF Router ID, the Cajun P550R does not immediately flush
the advertisements with the original Router ID. Instead these advertisements will be
flushed when they are aged from the database.
•When a virtual link is created on the Cajun P550R router, the router cannot detect if
the remote router is an ABR to area 0.0.0.0.
•There may be a loss of Web connectivity for about 10 seconds during LSA updates in
a large OSPF network.
Piggyback Ports
NOTE: If a router port for intelligent multicasting is mirrored with a piggyback port, the
piggyback port is listed instead of the router port.
RMON
NOTE: On Gigabit Ethernet port, under heavy utilization, 30 minute RMON stats always
show utilization as 0.

Cajun P220, P550, P550R Switch Release Notes, Release 4.0.1 18
SNMP
NOTES:
•Cold start traps cannot be transmitted out of inband interfaces when Spanning Tree
is enabled.
•ipAddrTable does not display inactive interfaces (VLANs). An inactive interface
occurs when there are no active ports on a VLAN.
•You cannot have more than 10 SNMP community strings per switch.
Spanning Tree
NOTES:
•The Cajun P550 48-port Media Module (M5548E-100TC) supports Spanning Tree
for each group of eight ports at the internal switch port. Spanning Tree functionality
is disabled by default. If per-port STP is required, it is recommended that you use a
Cajun P550 20-port Module (M5520-100TX) or Cajun P550 Layer 3 12-port Copper
Module (M5512R-100TX).
•Release 4.0.1 does not allow modification of the Spanning Tree and Fast Start
features on the CPU switch port. When you modify all switch ports, the Spanning
Tree and Fast Start features will be not be applied for the CPU switch port and the
corresponding status line does not display.
•Spanning tree convergence may take longer than 30 seconds in complex networks
after a topology change
Problem: When IEEE 802.1D spanning tree is used with hunt groups, the non-flood
ports are shown as forwarding, even if the hunt group is blocked.
Workaround: The flood port of the hunt group shows the actual state of the spanning
tree. View the flood port to see the actual state of the spanning tree.

Cajun P220, P550, P550R Switch Release Notes, Release 4.0.1 19
PPP and Telnet
NOTES:
•A Telnet session to the serial port via PPP may time out during attempts to transfer
large files, such as executable images, to a TFTP server over the same link. However,
the file transfer is not terminated. An in-progress TFTP file transfer continues and
ends only after the file transfer is completed.
•File transfer via TFTP over PPP links may terminate before completion if the dialin
PC is used TFTP server.
•A new baud rate may take effect before the current PPP connection is terminated if
the relevant baud rate change command is entered more than once resulting in
termination of PPP connection. This requires re-establishment of a PPP connection.
Time Zones
Problem: The System Clock may be incorrect after an upgrade to 4.0.
Workaround: Check the System Clock and reset it, if necessary. For information about
resetting the System Clock, refer to the Cajun P550/P220 Switch Operations Guide.
Problem: To support SNTP, the internal clock was changed from local time to GMT. The
System Clock is now displayed by converting the internal representation (GMT) to local
time by accounting for time-zone and summer-time hour configurations.
An upgrade routine has been added that changes the System Clock for all switches
running 3.0 or higher, given the following assumptions:
•The switch is running Release 3.x,
•The time-zone is set properly in the 3.x image, and
•The time-zone defined supports the North American Daylight Savings Time rules.
If any of these assumptions are false, the System Clock will be incorrect.
Workaround: Check the System Clock and reset it, if necessary. For information about
resetting the System Clock, refer to the Cajun P550/P220 Switch Operations Guide.

Cajun P220, P550, P550R Switch Release Notes, Release 4.0.1 20
VLAN Issues
NOTE: If the Switch Port attribute Automatic VLAN Creation is set to Enabled, the
Allow Learning attribute must also be set to Enabled.
Configuring VLANs
NOTES:
•In certain large configurations, the switch powers up very slowly.
•If you set a port’s VLAN trunking mode to Clear, make sure not to change the VLAN
Binding Type from the default value: Static.
•If you are using both the VLAN auto-learning feature and the Binding Type Bind to
Received or Bind to All, make sure that you set the binding type before you set
Auto-learn to enable or else the port may not be automatically added to the VLAN.
Duplicate VLAN Error Message
NOTE: When you add a VLAN and then refresh your browser page, you may receive an
error message stating that the VLAN name is already in use.
IEEE 802.1Q Packets
Problem: When a tagged IEEE 802.1Q packet arrives on a port that is “bind-to-all” and
the VLAN does not exist on the switch, the packet is forwarded on to the VLAN assigned
to the port default VLAN for that port.
Workaround: To prevent unintended forwarding of unknown VLAN traffic to the port
default VLAN, configure the port default VLAN to the “discard” VLAN. However, please
note that automatic VLAN creation will not work if the port default VLAN is the
“discard” VLAN, because the switch does not learn for this VLAN.