3Com 3800 STPD 1 STPD 2

7-6 CHAPTER 7: SPANNING TREE PROTOCOL (STP)

STP Conﬁgurations When you assign VLANs to an STPD, pay careful attention to the STP

conﬁguration and its effect on the forwarding of VLAN trafﬁc.

Figure 7-4 illustrates a network that uses VLAN tagging for trunk

connections. The following four VLANs have been deﬁned:

■Sales is deﬁned on Switch A, Switch B, and Switch M.

■Personnel is deﬁned on Switch A, Switch B, and Switch M.

■Manufacturing is deﬁned on Switch Y, Switch Z, and Switch M.

■Engineering is deﬁned on Switch Y, Switch Z, and Switch M.

■Marketing is deﬁned on all Switches (Switch A, Switch B, Switch Y,

Switch Z, and Switch M).

Two STPDs are deﬁned:

■STPD1 contains VLANs Sales and Personnel.

■STPD2 contains VLANs Manufacturing and Engineering.

The VLAN Marketing is not assigned to a STPD.

Figure 7-4 Multiple Spanning Tree Domains

Sales, Personnel, Marketing

STPD 1 STPD 2

Manufacturing, Engineering, Marketing

Sales, Personnel, Manufacturing, Engineering, Marketing

Switch A Switch Y

Switch Z

Switch M

Switch B

SW3800.BK Page 6 Tuesday, May 5, 1998 5:20 PM

Contents

Main 3Com Corporation 5400 Bayfront Plaza Santa Clara, California 95052-8145 CSA Statement FCC Statement Electromagnetic Compatibility VCCI Statement Information To The User Page C ONTENTS VERVIEW 3800 O WITCH NSTALLATION WITCH S HE I ETUP AND OMMANDS C Page PANNING OUTING R NICAST ROTOCOL REE 9 A B UPPORT ECHNICAL D Page A BOUT T HIS G Finding Information in This Guide This table shows where to nd specic information in this guide. Conventions guide. Table 1 Notice Icons Table 2 Text Conventions Command Syntax Symbols Table 3 Command Syntax Symbols Line-Editing Commands Related Publications Page 1 About the Switch 3800 Summary of Features Page Dual-homed Page Network Conguration Example Page Switch 3800 Front View Table 1-1 Media Types and Distances Table 1-2 Switch 3800 LEDs Switch 3800 Rear View Factory Defaults Table 1-3 Switch 3800 Factory Defaults 2 Following Safety Information Determining the Switch 3800 Location Installing the Switch 3800 Page Connecting Equipment to the Console Port Figure 2-2 shows the pin-outs for a 9-pin to RS-232 25-pin null modem cable. Figure 2-3 shows the pin-outs for a 9-pin to 9-pin PC-AT serial null modem cable. Powering-up the Switch Checking the Installation Logging on for the First Time Page Page 3 Security Access Levels Page Page Methods of Managing the Using Telnet Page Page Using SNMP Page Page Table 3-4 describes SNMP conguration commands. Table 3-4 SNMP Conguration Commands Checking Basic Connectivity Conguring Ports Page Load Sharing Page SmartRedundancy Port Commands Table 3-8 Port Commands (continued) 4 Understanding the Command Syntax Page Page Line-Editing Commands command-line interface. Table 4-1 Command Syntax Symbols (continued) Table 4-2 Line-Editing Commands Command History Substitution can display a list of these commands by typing Common Commands Commands specic to a particular feature are described in the other chapters of this guide. Table 4-3 Common Commands Switch 3800 Commands General Switch Commands Table 4-4 describes general Switch commands. Table 4-4 General Switch Commands User Account Commands Table 4-5 describes user account commands. Table 4-4 General Switch Commands (continued) Table 4-5 User Account Commands Switch Management Commands Table 4-6 describes Switch management commands Table 4-6 Switch Management Commands VLAN Commands Table 4-7 describes VLAN commands. Table 4-6 Switch Management Commands (continued) Table 4-7 VLAN Commands Protocol Commands Table 4-8 describes protocol commands. FDB Commands Table 4-9 describes FDB commands. Table 4-8 Protocol Commands Table 4-9 FDB Commands Port Commands Table 4-10 describes port commands. Table 4-9 FDB Commands (continued) Table 4-10 Port Commands PACE Commands Table 4-11 describes PACE commands. Table 4-10 Port Commands Table 4-11 PACE Commands STP Commands Table 4-12 describes STP commands. Table 4-12 STP Commands Table 4-12 STP Commands (continued) Basic IP Commands Table 4-13 describes basic IP commands. Table 4-13 Basic IP Commands IP ARP Commands Table 4-14 describes IP ARP commands. Table 4-13 Basic IP Commands (continued) Table 4-14 IP ARP Commands IP Route Table Commands Table 4-15 describes IP route table commands. ICMP Commands Table 4-16 describes the commands used to congure the ICMP protocol. Table 4-15 IP Route Table Commands Table 4-16 ICMP Commands Table 4-16 ICMP Commands (continued) RIP Commands Table 4-17 describes the commands used to congure the RIP protocol. Table 4-17 RIP Commands Table 4-17 RIP Commands (continued) Logging Commands Table 4-18 describes Switch logging commands. Table 4-18 Logging Commands Conguration and Image Commands Table 4-19 describes conguration and image commands. Table 4-18 Logging Commands (continued) Table 4-19 Conguration and Image Commands Table 4-19 Conguration and Image Commands (continued) 5 Overview of Virtual LANs Page Marketing Finance Page Accounting Engineering Page Figure 5-4 illustrates the physical view of a network that uses tagged and untagged trafc. Figure 5-4 Physical diagram of tagged and untagged trafc Figure 5-5 shows a logical diagram of the same network. Figure 5-5 Logical view of tagged and untagged trafc Marketing Page Page Page Conguring VLANs on the Switch 3800 Table 5-1 describes the commands used to congure a VLAN. VLAN Conguration Examples The following example creates a port-based VLAN named accounting, assigns the IP address 132.15.121.1, and assigns ports 1, 2, 3, and 6 to it: Table 5-1 VLAN Conguration Commands Displaying VLAN Settings Page Deleting and Resetting VLANs Page 6 D FDB Overview of the Page Conguring FDB Entries Displaying FDB Entries Removing FDB Entries 7 Overview of the Spanning Tree Protocol Page Page Spanning Tree Domains Page STP Congurations STPD 1 STPD 2 Sales, Personnel, Marketing Manufacturing, Engineering, Marketing Sales, Personnel, Manufacturing, Engineering, Marketing Page STP Congurations to Avoid Marketing & Sales Marketing, Sales & Engineering Sales & Engineering Creating STP Domains Marketing & Sales Marketing, Sales & Engineering Sales & Engineering Enabling STP on the Switch Conguring STP Table 7-1 STP Conguration Commands (continued) Displaying STP Settings Sample output from the command is as follows: Disabling and Resetting STP 8 Overview of IP Unicast Routing Page Page Conguring IP Unicast Routing Verifying the IP Unicast Routing Conguring DHCP/BOOTP Relay Table 8-1 describes the commands used to congure basic IP settings on the Switch. Table 8-1 Basic IP Commands Table 8-2 describes the commands used to congure the IP route table. Table 8-3 describes the commands used to congure RIP. Table 8-1 Basic IP Commands (continued) Table 8-2 Route Table Conguration Commands Table 8-3 RIP Conguration Commands Table 8-3 RIP Conguration Commands (continued) Table 8-4 describes the commands used to congure the ICMP protocol. Table 8-3 RIP Conguration Commands (continued) Table 8-4 ICMP Conguration Commands Routing Conguration Example Figure 8-2 Unicast Routing Conguration Example = IP traffic = NetBIOS traffic Displaying Router Settings commands listed in Table 8-5. Table 8-5 Router Show Commands Resetting and Disabling Router Settings Table 8-5 Router Show Commands (continued) Table 8-6 Router Reset and Disable Commands Table 8-6 Router Reset and Disable Commands (continued) 9 S Status Monitoring Page Page Port Statistics Page Port Errors Switch Logging Page Page Logging Commands The commands described in Table 9-4 allow you to do the following: Table 9-4 Logging Commands RMON Page Page Page Page Page 10 O Upgrading the Software Saving Conguration Changes Boot Option Commands Page A Important Safety Information Page Page Linformation de Scurit Importante Page Page Page Wichtige Sicherheitsinformat ionen Page Page Page Page B Physical Dimensions Page C LEDs Using the Command-Line Interface Page Page Page Page D Online Technical Services Page Support from Your Network Supplier D-4 APPENDIX D: TECHNICAL SUPPORT Support from 3Com Regional Sales Office Telephone Number Regional Sales Office Telephone Number Returning Products for Repair Page G Page Page Page I Numerics A B C L M N O P T U V W Page 3Com Corporation LIMITED W H S STANDARD WARRANTY S W ARRANTIES E L IMITATION OF L IABILITY G OVERNING L AW