日常维护命令介绍© 2011 Brocade Communications Systems, Inc.10Console PortDB-9 male interface. VT-100 terminal - straight-through cable (female to female not a null-modem).The VT-100 configuration is: 9600 Baud 8 Data Bits Parity = None Stop Bits = 1 Flow Control = None For MODEM Cross-Over cable (typically a DB-9F to DB-25F cable)© 2011 Brocade Communications Systems, Inc.11Stackables Layout1 23 45 67 8Link / Act© 2011 Brocade Communications Systems, Inc.FDX 10012Command Line Interface (CLI) BasicsConfigure via character-based terminal/session Direct Connect to the Serial Port or Telnet to the System “?” at any prompt shows available commands SW-FI4802-PREM>? enable fastboot ping show stop-traceroute traceroute Enter Privileged mode Select fast-reload option Ping IP node Display system information Stop current TraceRoute TraceRoute to IP Node“?” At end of character string SW-FI4802-PREM> s? will list commands show Display system information that begin with stop-traceroute Stop current TraceRoute that string SW-FI4802-PREM> stop-traceroute ^? “^?” At the end of a character string will list <cr> the next string SW-FI4802-PREM> stop-traceroute <cr> parameter “^” means space <TAB> can be used for “?”Commands can be abbreviated© 2011 Brocade Communications Systems, Inc.13CLI Basics – Command TreeUser Level View basic information?ping <ip address>Verify connectivity (Ping command) User LevelPrivileged Level• Enter through the “enable” command • Can be password protected • View detailed information (Show) • Execute System-wide features (boot system)showenable <password>Privileged LevelConfiguration Level• Enter through the “configure terminal” command • Make global or local system changes (VLANs) • Save changes with “write memory”© 2011 Brocade Communications Systems, Inc.Configuration Level14CLI BasicsUser level:Privileged level:SW-FastIron# ?Access list Arp table Power supply/fan/temperature Configuration data in flash Print system default settings Flash memory contents Port status IP address setting System log MAC address table Gig port SX/LX/LHA/LHB Module type and status 802.1p tagged priority setting Configuration of the 4 QOS Relative utilization list Scheduled system reset Rmon status Current running config Snmp statistics Spanning tree status Packet statistics15SW-FastIron>? access-list enable Enter Privileged mode arp fastboot Fast-reload option chassis ping Ping IP node clock show Display system info configuration stop-traceroute Stop current TraceRoute default traceroute TraceRoute to IP Node flash SW-FastIron> enable interfaces Password: ip logging mac-address media module Different prompts indicate priority-mapping the level you are at: qos-profiles relative-utilization reload User = “>” rmon Privileged =“#” running-config Configuration = “(config)#” snmp span statistics© 2011 Brocade Communications Systems, Inc.CLI Basics - CONFIG commandsSW-FastIron> enable No password has been assigned yet... SW-FastIron# configure terminal SW-FastIron(config)# ?Notice the CONFIG prompt:Config LEVEL (contd) spanning-tree static-mac-address vlan tag-type ip-proto ip-subnet ipx-proto ipx-network atalk-proto decnet-proto netbios-proto other-proto web-management trunkConfig LEVEL SW-FastIron(config)#? end exit no show write aaa boot broadcast-limit chassis clock dhcp-gateway-list enable hostname interface ip ipx© 2011 Brocade Communications Systems, Inc.Config LEVEL (contd) l3-ip-switch l3-ipx-switch l3_test lock-address logging mac-age-time mac mirror-port telnet-server telnet-timeout server password-change radius-server rmon snmp-server sntp16CLI BasicsPrivilege level NetIron> enable {superuser password} NetIron#Executing system-wide commands Show Information Reload the systemCopy image files or configuration files Set the system clock CONFIG LevelBigIron# conf tConfigure the SystemBigIron(config)#(stands for “configure terminal”)Assign system IP address Setup the Interfaces Setup DNS information (DNS server, domain)© 2011 Brocade Communications Systems, Inc.Indicate IP address of Time Server (NTP) or RADIUS server17CLI BasicsInterface Level SW-ServerIron(config-if-1)# SW-ServerIron(config)# int e1 (e1 = ethernet port #1)Port parameters ( type “?” at prompt for options) SW-ServerIron(config-if-1)# ? enable port-name ipg100 phy-mode auto-gig Current Context is shown by prompt disable dhcp-gateway-list ip-policyqos-priorityspeed-duplex spanning-tree ipg1000macipg10monitorflow-controlSW-FastIron(config-if-e100-1)# (Interface #1) TurboIron(config-vif-1)# NetIron(config-vlan-3)# (Virtual Interface #1 - applies to routers only) (Virtual LAN #3) (Transparent Cache named “CacheFour”) (Virtual Server named “VIP1”) SW-ServerIron(config-tc-CacheFour)# SW-ServerIron(config-vs-VIP1)#© 2011 Brocade Communications Systems, Inc.18CLI BasicsMove back up the menu tree using “exit” SW-ServerIron(config-rs-c1)# exit SW-ServerIron(config)# exit SW-ServerIron# exit SW-ServerIron>Display the running-configUse “end” or Cntl-Z to return to “#” prompt SW-ServerIron# write terminalDisplay the saved startup-config Erase the Startup-ConfigSW-ServerIron# show running-config SW-ServerIron# show config SW-ServerIron# erase startup-configThe CLI supports {up / down arrow} for access to the last commands entered SW-ServerIron(config)# ping 10.1.1.1 Invalid input -> ping 10.1.1.1 Type ? for a list SW-ServerIron(config)#exit© 2011 Brocade Communications Systems, Inc.SW-ServerIron#In your terminal emulation program, press the “up” arrow19Identifying Software ImagesBrocade products run one of three types of flash images: Router Code Switch CodeBase Router Code View the Current Running ImageBigIron# BigIron# show version SW: Version 07.5.01T23 Copyright (c) 1996-2001 Brocade Networks, Inc. Compiled on Jun 04 2001 at 15:50:59 labeled as VM1R07501 (2852369 bytes) from Primary vm1r07501.bin HW: Chassis 4000 Router, SYSIF version 21© 2011 Brocade Communications Systems, Inc.20File ManagementTwo Image Storage Areas View the Flash: BigIron Router#sho flash Active management module: Code Flash Type: AMD 29F032B, Size: 64 * 65536 = 4194304, Unit: 2 Boot Flash Type: AMD 29F040, Size: 8 * 65536 = 524288 Compressed Pri Code size = 3485205, Version 07.5.01T53 (b2r07501.bin) Compressed Sec Code size = 3494253, Version 07.5.02T53 (b2r07502.bin) Maximum Code Image Size Supported: 3866112 (0x003afe00) Boot Image size = 149324, Version 07.02.01 (m2b07201.bin) Primary & SecondaryPrimary FlashBoot ImageSecondary Flash© 2011 Brocade Communications Systems, Inc.21File Management (continued)Specify where to boot from: Primary Flash TFTP Server Secondary Flash BootP ServerTFTP Server Image CodeManagement ModuleSystem Flash Primary Flash SecondaryWhere you enter the command also dictates when to loadRAM• PRIVILEGED level - IMMEDIATE reboot/reloadSW-FastIron# boot system flash secondary SW-FastIron# b s f s• CONFIG level - Load at next scheduled reboot orBigIron#(config)# boo sy f s BigIron#(config)# wri memabbreviated but unique command lineBigIron# reload at 06:00:00 01-19-04© 2011 Brocade Communications Systems, Inc.22File Copy commandsFrom/To TFTP Servers Exec Privileged Level: From/To Primary or Secondary FlashTFTP ServerManagement Module SystemFlash Primary Flash SecondaryCopies from the TFTP server the file “vm1r07501.bin ” and stores it to the secondary flash area. NetIron# copy flash tftp 192.22.33.44 vm1r07501.bin secondary • Copies the system image from the secondary flash area and stores it to the TFTP server as filename “vm1r07501.bin”. TurboIron# copy flash flash ? primary Copy secondary to primary secondary Copy primary to secondary TurboIron# copy flash flash primary • Copies the system image from the secondary flash area to the primary. SW-FastIron# copy running-config tftp 192.22.33.44 new.cfg • Copies from the current running config (not the stored config) and writes it to the TFTP server as filename “new.cfg”. NetIron# copy tftp flash 192.22.33.44 nib06007.bin boot • Copies the boot image from tftp server to the boot memory location of flash.(“boot” is a hidden parameter)NetIron# copy tftp flash 192.22.33.44 vm1r07501.bin secondaryRAM© 2011 Brocade Communications Systems, Inc.23Upgrading to 7.602 and BeyondTo upgrade a FI-4802 or a chassis from a pre07.6.01 release to release 07.6.02, do the following:TFTP ServerManagement Module SystemFlash Primary Flash SecondaryM2R07.6.0.2Boot CodeRAM1. Upgrade the boot code to version 07.6.02. 2. Upgrade the flash code to version 07.6.01 3. reload the system 4. Upgrade the flash code to version 07.6.02 5. reload the systemStep 1B2R07.6.0.2 Step 4Step 5 reloadImage CodeStep 3 reload B2R07.6.0.1 Step 2 B2R07.5.0.X24Upgrading directly from pre-7.601 to 7.602 is not possible due the required compression algorithm.© 2011 Brocade Communications Systems, Inc.M2R07.5.0.XWrite/Show Config commandsMost configuration changes take effect immediately. To make permanent (i.e., persistent after a re-boot) save the changes to FLASH:TurboIron# write memorySW-FastIron# write terminal orTerminalSW-FastIron# show running-configTo see the start-up configuration file:NetIron# show configurationNote: The running config and stored config (startup config) may or may not be the same. The running config is lost during a power © 2011 Brocade Communications Systems, Inc. cycle.reloadTo see the running configuration:Running Config write memoryRAMStartup ConfigFLASH25Switch and Router show commands:show version show stat show ip show interfaceShow Commands - Switch & RouterSoftware version and uptime Interface statistics Interf status (up or down etc.) IP info (address, mask etc.) MAC forwarding table Flash memory images Spanning tree infoshow spanshow mac-address show flash show vlanshow mac-address stat# of MACs learned per portshow telnet show trunk in show tech-support© 2011 Brocade Communications Systems, Inc.IP addr of active telnet sessionsConfigured VLANsShows technical details for assistance technical support.Config’d and active trunk groupswithtroubleshooting issues when working26Show Commands - Router onlyRouter-only show commands: NetIron# show arp NetIron# show ip interface NetIron# show ip cache NetIron# show ip ospf NetIron# show ip route NetIron# show ip traffic statistics NetIron# show ip dvmrp NetIron# show ipx cache NetIron# show ipx interface NetIron# show ipx routes NetIron# show ipx servers NetIron# show ipx traffic DVMRP information Summary of IPX information IPX interface information IPX route information IPX servers defined for the router IPX traffic statistics ARP cache ip interface information IP host/MAC table OSPF information IP routes and their status IP (ICMP, UDP, TCP, RIP) trafficMany of the above commands have several branches. An example isNetIron# show ip ospf neighbor© 2011 Brocade Communications Systems, Inc.Neighbor router information27Reference the manual for a complete list of all commands.Clear CommandsClearing forwarding and route tables Switch / Router clear commands:(SW-FastIron, TurboIron, BigIron) TurboIron# clear arp TurboIron# clear mac-address TurboIron# clear statistics NetIron# clear logging Router-only clear commands:(NetIron, TurboIron, BigIron) NetIron# clear ip route NetIron# clear ip cache NetIron# clear ipx route NetIron# clear ipx cache Clearing Individual Entries The mac <mac-addr> <mask> parameter clears only the entries that match the specified address and mask. The vlan <vlan-id> parameter clears only the entries that match the specified VLAN. clear mac-addressRemoves learned MAC address entries from the MAC address table. EXAMPLE:BigIron# clear mac-address © 2011 Brocade Communications Systems, Inc. ethernet 1/1Clears ARP table Clears the MAC forwarding tables Clears all statistic counters. Clears the system log Clears IP route tables. Clears IP host/MAC tables Clears IPX route tables. Clears IPX cache28Ping CommandHelpful when trying to verify connectivity Cannot be entered when in “configure” mode A few sample PING commands: SW-FastIron> ping 192.190.10.10 SW-FastIron# ping 192.190.10.10 count 100 SW-FastIron> ping 192.190.10.10 size 1200 SW-FastIron# ping 192.190.10.10 ttl 5 c 10 s 200 Issues 10 pings with a time to live of 5 and each ping is 200 bytes long Use “?” after the address for other options Syntax: ping <ip addr> | <hostname> [source <ip addr>] [count <num>] [timeout <msec>] [ttl <num>] [size <byte>] [quiet] [numeric] [no-fragment] [verify] [data <1-to-4 byte hex>] [brief]© 2011 Brocade Communications Systems, Inc.29User Access Control (Overview)Web BrowserIronViewLANConsole ConnectionSW-FI4802>enable En_password SW-FI4802#IP Add: 192.22.33.45TelnetTelnet 192.22.33.45 Telnet password:Tel_Passwd SW-FI4802>enable En_password SW-FI4802#Locally Defined Passwords •Enable Password (three levels) •Telnet Password •Web Password (SNMP Community String) •Username / Password lists© 2011 Brocade Communications Systems, Inc.30CLI Basics - PasswordsFactory Default = no Enable passwords Passwords can be up to 32 characters long Multiple levels of “Enable” password access Access depends on which password you useSuper User - Unlimited access, can change all parameters Configure Port - Change interface level parameters Read Only - View only, no changing allowedBigIron(config)# enable super-user-password SuPswd BigIron(config)# enable port-config-password PCPswd BigIron(config)# enable read-only-password ROPswd BigIron> enable PCPswd or BigIron> enable Password:If the system password is not yet set, the system warns you BigIron> enable No password has been assigned yet...© 2011 Brocade Communications Systems, Inc.31Password ExamplesDefining the Super-User (Enable) password Port Config (Enable) password accesses a limited set of commandsSW-ServerIron(config)#enable port-config-password PCPswd SW-ServerIron>enable PCPswd SW-ServerIron#conf t SW-ServerIron(config)#? end exit quit no show interface SW-ServerIron(config)#enable read-only-password ROPswd SW-ServerIron>enable ROPswd SW-ServerIron#? exit quit ping show telnet SW-ServerIron(config)#enable super-user-password SuPswd SW-ServerIron(config)#quit SW-ServerIron> enable SuPswdRead Only Password Limits user to Exec User and Exec Privileged levels© 2011 Brocade Communications Systems, Inc.32CLI Basics - Passwords, recoveringYou can recover from a forgotten password Have terminal session plugged into serial port, then:Reboot the system Within 2 seconds, enter ‘b’ to initiate the boot monitorBOOT MONITOR> boot system flash primary BOOT MONITOR> no password (cannot be abbreviated)Requires direct access to the Serial Port and a System ResetThis bypasses the system password check Reassign Super-User password & save configSW-FastIron(config)#write memory© 2011 Brocade Communications Systems, Inc.SW-FastIron> enable No password has been assigned yet… SW-FastIron#SW-FastIron(config)#enab super-user NewPassword(assigns a new password)33Also specify passwords for:Telnet Access Where Passwords can be changed fromoptions: <any|serial-port-only|telnet-only>SW-FastIron(config)#enable telnet password TelNetPswd SW-FastIron(config)#password-change serial-port-onlyCLI Basics - PasswordsUsernames / Password combinations(config)#username BigKahuna priv 0 password BKpswdSpecify Username, Password and Privilege Level A Super-User account (or Super-User enable password) must be set before you can create lower-access accounts Passwords are stored in Config File ENCRYPTED (default)or you can turn off encryption Privilege level: 0=Super-User, 4=Port-Config, 5=Read-onlyUsername Lists are applied with AAA commands© 2011 Brocade Communications Systems, Inc.(config)# no service password-encryption34Passwords - aaa authentication typesAuthentication for the following access typesSyntax:aaa authentication <snmp-server|webserver|enable|login> defaultaaa authentication {what type of access} default {how to validate}<method1>[<method2> <method2> <method3> <method4> <method5> <method6> <method7>]• aaa authentication snmp-server ...SNMP applications - IronView, HPOV, Spectrum, etc.• aaa authentication web-server ...Web Browser to Brocade Switches and Routers• aaa authentication enable ...“enable” command to gain Privileged and CONFIG level access• aaa authentication login ...TELNET access to the Brocade Switch/Router© 2011 Brocade Communications Systems, Inc.35Passwords - aaa authentication methodsAthentication methodsSyntax: aaa authentication <snmp-server|web-server|enable|login> defaultIf a validation method is NOT configured, use next method<method1> [<method2> <method2> <method3> <method4> <method5> <method6> <method7> ]• TACACS, TACACS+, RADIUSQuery a TACACS, TACACS+ or RADIUS server for username/password • local Use locally defined username/password combinations • line Use the TELNET access password • enable Use the “enable” passwords (super-user, port-config, read-only)© 2011 Brocade Communications Systems, Inc.36Remote Access ServerTACACS Server2. Password checkIP Add 192.23.33.453. Password VerifiedemptyTelnet password: Tel_Passwd1. Request for AccessIP Add: 192.22.33.45TelnetTelnet 192.22.33.45 Telnet password:Tel_Passwd SW-FI4802>enable En_password SW-FI4802#AAA Example Type of Access Validation Method Login 1. TACACS 2. Line Enable 1. TACACS 2. Local 3. Enable4. Access Granted© 2011 Brocade Communications Systems, Inc.37Passwords - aaa authentication examplesSyntax:aaa authentication {what type of access} default {how to validate}Examples•aaa authentication login default localFor TELNET access (“login”), use the locally defined usernames•aaa authentication enable default radius localTo gain privileged /CONFIG access (“enable” command), query a configured RADIUS server; if not configured, fallback to locally defined usernames•aaa authentication web default radius local enableThe Web Browser will first look at 1) RADIUS usernames, if not configured, 2) locally defined usernames, if not configured 3) use the “enable” super-user, port-config, and read-only passwords© 2011 Brocade Communications Systems, Inc.38SNMP ConfigurationSNMP required information:SW-FastIron(config)# ip address 192.22.33.45 255.255.255.0 SW-FastIron(config)# ip default-gateway 192.22.33.1 SW-FastIron(config)# snmp-server contact “Bill Clinton” SW-FastIron(config)# snmp-server location the_white_house SW-FastIron(config)# snmp-server host 192.22.33.55 public SW-FastIron(config)# snmp-server community notsafe ro SW-FastIron(config)# snmp-server community safe rwNote:The first two commands are valid for switches only. Routers would assign an IP address at the interface level, not at the global level.NetIron(config) interface ethernet 9 NetIron(config-if-9)# ip address 192.22.33.45 255.255.255.0© 2011 Brocade Communications Systems, Inc.39Web Browser GUI ConfigEnabled with web browserUsername & Password AccessUser Name PasswordRead Only get publicRead / Write set<user configured community string> Only one session can be Read/WriteMultiple Read-only sessions(passwordprotected access)Web Browser GUI Config -Passwords Web Browser Username/PasswordRead-only default Username/Password:Username : getPassword : publicMust set a password via the Command Line Interface (CLI)The default WEB GUI passwords are the SNMP Community names BigIron(config)# snmp-server community not_safe roBigIron(config)# snmp-server community safe rw Requires an IP address to “Web” toUse the Serial Port to configure IP addressSwitches -IP address applies to all ports by defaultRouters -IP address is specific to one port (or group of ports)Controlling AccessYou can restrict Web,Telnet and SNMP access to a single management address:BigIron(config)#web client 209.157.22.39BigIron(config)#snmp-client 209.157.22.14BigIron(config)#telnet client 209.157.22.26BigIron(config)#all-client 209.157.22.69 for all three types To disable Management completely:BigIron(config)#no web-managementBigIron(config)#no telnet serverBigIron(config)#no snmp-serverSearching and Filtering from the Command LinePipe “|” commands modify the output of show commands according to operatorSupports searching and filteringMatching uses regular expressions Examples:show int| begin3/5show int| include MTUshow int brief | exclude downOnly one pipe allowed per command Syntax: show command |Operator <matching string>Searching and Filtering at the More PromptEquivalents to the pipe commands operations can be done at the More promptAt the More prompt, enter a: /, + or -operator:/(slash) like “begin” operator+(plus) like “include” operator-(minus) like “exclude” operatorThen enter a regular expressionThe particular word, number, or Special Character to searchonPress Return/Enter to activate the command Syntax: <more prompt> operator<matching string>Regular ExpressionRegular Expressions contain special characters in the matching string to specify search patterns.Syntax: show command |Operator < special character in matching string>Some tips and matching examples:Regular characters match themselves123 matches 123Dot “.” matches any single character1.3 matches 123, 1A3, 1/3, etc.Caret “^” matches beginning of a line^123 matches lines that start with 123Dollar sign “$” matches the end of a line123$matches lines that end with 123Underscore “_” matches things at beginning or end of words, such as space, comma, parentheses, curly braces, beginning of line, or end of line, ex: _123_matches (123,456) but not 1234Grouping ExamplesBrackets “[]” are used to specify a range of values for a single character to be matched (a “character class”)[123]matches 1, 2, or 3[1-5]matches 1, 2, 3, 4, or 5Caret “^” as the first character inside brackets is used to invert the set of values[^1-3]matches any character other than1, 2, or 3Vertical bar “|” specifies alternative patterns123|456 will match 123or 456Parentheses group characters into a larger pattern Question mark “?” matches zero or one of the preceding pattern123?matches 12or 123(123)?matches nothing or 123To enter question mark instead of invoking help, press Ctrl-V first Asterisk “*” matches zero or more of the preceding pattern123*matches nothing, 123, 1233, 12333, etc.(123)*matches nothing, 123, 123123, 123123123, etc.Plus “+” matches one or more of the preceding patternOther attributes assigned to a port NetIron(config-if-8)# show interface briefPort Link State Duplex Speed Tag Priority MAC Trunk01 Down None None None No Normal 00e0.5200.0385 102 Down None None None No Normal 00e0.5200.0386 103 Down None None None No Normal 00e0.5200.0387 None 04 Down None None None No Normal 00e0.5200.0388 None Current Link State Up or Down Spanning Tree State Forward, Listen, etc.802.1q Tagged or not 05 Down None None None No Normal 00e0.5200.0389 None 06 Down None None None No Normal 00e0.5200.038a None 07 Down None None None No Normal 00e0.5200.038b None 08 Down None None None No Normal 00e0.5200.038c None 09 Up Listen Full 100M Yes Normal 00e0.5200.038d None 10 Up Forward Full 100M No Normal 00e0.5200.038e None 11 Down None None None No Normal 00e0.5200.038f None 12 Down None None None No Normal 00e0.5200.0390 None 13 Down None None None No Normal 00e0.5200.0391 None 14 Down None None None No Normal 00e0.5200.0392 None 15 Up Forward Full 100M No Normal 00e0.5200.0393 None 16 Down None None None No Normal 00e0.5200.0394 None17 Up Forward Full 1G No Normal 00e0.5200.0395 NoneCurrent Duplex StateFull or HalfNone = no link state Current Speed 10M, 100M, 1GQoS Priority, Normal, High Is this port part of a Trunk Group?(Trunk Group #)Specific attributes of each port SpeedAuto-negotiate (default)Forced to 10 or 100Mbps-Full Duplex/Half DuplexExamples:NetIron> enable passwordhereNetIron# config termNetIron(config)# interface e8NetIron(config-if-8)# speed-duplex 100-halfNetIron(config-if-8)# speed 10-fullNetIron(config-if-8)# speed autoNetIron(config-if-8)# interface e12NetIron(config-if-12)# speed 100-fullNetIron(config-if-12)# endNetIron# write memVLANsVirtual Local Area NetworkA subgroup within a local area networkCreates a broadcast domain Done through softwareTypes of VLANsLayer 2 port-based VLAN Layer 3 protocol VLANsIP Protocol VLANS IP sub-net VLANs IPv6 VLANsIPX network VLANs IPX sub-net VLANs AppleTalk DECNet NetBIOSOther - (not any of the above supported protocols)© 2011 Brocade Communications Systems, Inc.50VLAN Concept - Layer 2 Port BasedVLAN 1 Port 1, Port 2, Port 3, Port 4Port 1Port 2Port 3Port 5 Port 6© 2011 Brocade Communications Systems, Inc.51VLAN - 802.1q TaggingTagging allows multiple port based VLANs to span switches over a single physical linkVLAN 3 VLAN 2VLAN Tagging is not needed...…if the ports are grouped with dedicated uplinks for each VLAN between switches...empty…there’s no question where broadcast traffic goes from port to portVLAN 3© 2011 Brocade Communications Systems, Inc.VLAN 252VLAN - 802.1q Tagging (continued)VLAN 3 VLAN 2Tagging allows multiple port based VLANs to span switches over a single physical linkVLAN Tagging is needed... …with a single link between switches and multiple VLANs...…there needs to be a mechanism for having the traffic from VLAN2 only go to the VLAN2 ports on the other side.emptyVLAN 3© 2011 Brocade Communications Systems, Inc.VLAN 253VLAN - 802.1q Tagging (Packet Format)6 bytes Destination Address 6 bytes Destination AddressUntagged Packet Format6 bytes Source Address 6 bytes Source Address 2 bytes Type Field 2 bytes Length FieldUp to 1500 bytes Data Field Up to 1496 bytes Data Field4 bytes CRC 4 bytes CRCEthernet II IEEE 802.36 bytes Destination Address 6 bytes Destination Address802.1q Tagged Packet Format6 bytes Source Address 6 bytes Source Address2 bytes 4 bytes 2 bytesUp to 1500Up bytes to 1500 bytes 4 bytes Type 802.1q Type Data Data CRC Field Tag Field Field Field 2 bytes 4 bytes 2 bytesUp to 1496Up bytes to 1496 bytes 4 bytes Length 802.1q Length Data Data CRC Field Tag Field Field Field4 bytes CRC 4 bytes CRCEthernet II with 802.1q tagIEEE 802.3 with 802.1q tagOctet 1Tag Protocol Id (TPID)Octet 21 2 3 4 5 6 7 8 Octet 4 802.1p VLAN ID (12 bits) (3 bits)© 2011 Brocade Communications Systems, Inc.54。