Red Hat Enterprise Linux 7 Networking Guide

Table of Contents PART I. BEFORE YOU BEGIN CHAPTER 1. OVERVIEW OF NETWORKING TOPICS 1.1. COMPARING IP TO NON-IP NETWORKS Categories of Network Communication 1.2. COMPARING STATIC TO DYNAMIC IP ADDRESSING 1.3. CONFIGURING THE DHCP CLIENT BEHAVIOR Requesting an IP Address Requesting a Lease Renewal 1.3.1. Making DHCPv4 Persistent 1.4. SETTING THE WIRELESS REGULATORY DOMAIN 1.5. CONFIGURING NETCONSOLE 1.6. USING NETWORK KERNEL TUNABLES WITH SYSCTL 1.7. MANAGING DATA USING THE NCAT UTILITY Installing ncat Brief Selection of ncat Use Cases PART II. MANAGING IP NETWORKING CHAPTER 2. GETTING STARTED WITH NETWORKMANAGER 2.1. OVERVIEW OF NETWORKMANAGER 2.1.1. Benefits of Using NetworkManager 2.2. INSTALLING NETWORKMANAGER 2.3. CHECKING THE STATUS OF NETWORKMANAGER 2.4. STARTING NETWORKMANAGER 2.5. NETWORKMANAGER TOOLS 2.6. USING NETWORKMANAGER WITH NETWORK SCRIPTS Running Network Script Using Custom Commands in Network Scripts Running Dispatcher scripts 2.7. USING NETWORKMANAGER WITH SYSCONFIG FILES 2.8. ADDITIONAL RESOURCES CHAPTER 3. CONFIGURING IP NETWORKING 3.1. SELECTING NETWORK CONFIGURATION METHODS 3.2. CONFIGURING IP NETWORKING WITH NMTUI 3.3. CONFIGURING IP NETWORKING WITH NMCLI 3.3.1. Brief Selection of nmcli Examples 3.3.2. Starting and Stopping a Network Interface Using nmcli 3.3.3. Understanding the nmcli Options 3.3.4. Using the nmcli Interactive Connection Editor 3.3.5. Creating and Modifying a Connection Profile with nmcli 3.3.6. Connecting to a Network Using nmcli 3.3.7. Adding and Configuring a Dynamic Ethernet Connection with nmcli Adding a Dynamic Ethernet Connection Configuring a Dynamic Ethernet Connection 3.3.8. Adding and Configuring a Static Ethernet Connection with nmcli Adding a Static Ethernet Connection 3.3.9. Locking a Profile to a Specific Device Using nmcli 3.3.10. Adding a Wi-Fi Connection with nmcli Changing a Specific Property Using nmcli 3.3.11. Configuring NetworkManager to Ignore Certain Devices 3.3.11.1. Permanently Configuring a Device as Unmanaged in NetworkManager Procedure Verification Steps Additional Resources 3.3.11.2. Temporarily Configuring a Device as Unmanaged in NetworkManager Procedure Verification Steps Additional Resources 3.4. CONFIGURING IP NETWORKING WITH GNOME GUI 3.4.1. Connecting to a Network Using the control-center GUI 3.4.2. Configuring New and Editing Existing Connections Using a GUI 3.4.2.1. Configuring New and Editing Existing Connections Using control-center 3.4.2.2. Configuring New and Editing Existing Connections Using nm-connection-editor 3.4.3. Common Configuration Options Using nm-connection-editor 3.4.4. Connecting to a Network Automatically with a GUI 3.4.4.1. Connecting to a Network Automatically with control-center 3.4.4.2. Connecting to a Network Automatically with nm-connection-editor 3.4.5. Managing System-wide and Private Connection Profiles with a GUI 3.4.5.1. Managing Permissions for a Connection Profile with nm-connection-editor 3.4.5.2. Managing Permissions for a Connection Profile with control-center 3.4.6. Configuring a Wired (Ethernet) Connection with a GUI 3.4.6.1. Configuring a Wired Connection Using control-center 3.4.6.2. Configuring a Wired Connection with nm-connection-editor 3.4.7. Configuring a Wi-Fi Connection with a GUI Connecting Quickly to an Available Access Point Connecting to a Hidden Wi-Fi Network Configuring a New Wi-Fi Connection Editing an Existing Wi-Fi Connection Basic Configuration Options for a Wi-Fi Connection Making Further Wi-Fi Configurations Saving Your New (or Modified) Connection 3.4.8. Configuring a VPN Connection with a GUI 3.4.8.1. Establishing a VPN Connection with control-center 3.4.8.2. Configuring a VPN Connection with nm-connection-editor 3.4.9. Configuring a Mobile Broadband Connection with a GUI 3.4.9.1. Configuring a Mobile Broadband Connection with nm-connection-editor 3.4.10. Configuring a DSL Connection with a GUI 3.4.10.1. Configuring a DSL Connection with nm-connection-editor 3.5. CONFIGURING IP NETWORKING WITH IFCFG FILES Configuring an Interface with Static Network Settings Using ifcfg Files Configuring an Interface with Dynamic Network Settings Using ifcfg Files 3.5.1. Managing System-wide and Private Connection Profiles with ifcfg Files 3.6. CONFIGURING IP NETWORKING WITH IP COMMANDS Assigning a Static Address Using ip Commands Configuring Multiple Addresses Using ip Commands 3.7. CONFIGURING IP NETWORKING FROM THE KERNEL COMMAND LINE 3.8. ENABLING IP MULTICAST WITH IGMP 3.9. ADDITIONAL RESOURCES Installed Documentation Online Documentation CHAPTER 4. CONFIGURING STATIC ROUTES AND THE DEFAULT GATEWAY 4.1. INTRODUCTION TO UNDERSTANDING ROUTING AND GATEWAY 4.2. CONFIGURING STATIC ROUTES USING NMCLI 4.3. CONFIGURING STATIC ROUTES WITH GUI 4.4. CONFIGURING STATIC ROUTES WITH IP COMMANDS 4.5. CONFIGURING STATIC ROUTES IN IFCFG FILES Static Routes Using the IP Command Arguments Format Static Routes Using the Network/Netmask Directives Format 4.5.1. Understanding Policy-routing 4.6. CONFIGURING THE DEFAULT GATEWAY CHAPTER 5. CONFIGURING NETWORK CONNECTION SETTINGS 5.1. CONFIGURING 802.3 LINK SETTINGS Ignoring link negotiation Enforcing auto-negotiation activation Manually setting the link speed and duplex Configuring 802.3 Link Settings with the nmcli Tool Configuring 802.3 Link Settings with nm-connection-editor 5.2. CONFIGURING 802.1X SECURITY 5.2.1. Configuring 802.1X Security for Wi-Fi with nmcli 5.2.2. Configuring 802.1X Security for Wired with nmcli 5.2.3. Configuring 802.1X Security for Wi-Fi with a GUI 5.2.4. Configuring 802.1X Security for Wired with nm-connection-editor Configuring TLS Settings Configuring FAST Settings Configuring Tunneled TLS Settings Configuring Protected EAP (PEAP) Settings 5.3. USING MACSEC WITH WPA_SUPPLICANT AND NETWORKMANAGER 5.4. CONFIGURING IPV4 SETTINGS Configuring IPv4 Settings with control-center Setting the Method for IPV4 Using nm-connection-editor 5.5. CONFIGURING IPV6 SETTINGS 5.6. CONFIGURING PPP (POINT-TO-POINT) SETTINGS CHAPTER 6. CONFIGURE HOST NAMES 6.1. UNDERSTANDING HOST NAMES 6.1.1. Recommended Naming Practices 6.2. CONFIGURING HOST NAMES USING TEXT USER INTERFACE, NMTUI 6.3. CONFIGURING HOST NAMES USING HOSTNAMECTL 6.3.1. View All the Host Names 6.3.2. Set All the Host Names 6.3.3. Set a Particular Host Name 6.3.4. Clear a Particular Host Name 6.3.5. Changing Host Names Remotely 6.4. CONFIGURING HOST NAMES USING NMCLI 6.5. ADDITIONAL RESOURCES CHAPTER 7. CONFIGURE NETWORK BONDING 7.1. UNDERSTANDING THE DEFAULT BEHAVIOR OF MASTER AND SLAVE INTERFACES 7.2. CONFIGURE BONDING USING THE TEXT USER INTERFACE, NMTUI 7.3. NETWORK BONDING USING THE NETWORKMANAGER COMMAND LINE TOOL, NMCLI 7.4. USING THE COMMAND LINE INTERFACE (CLI) 7.4.1. Check if Bonding Kernel Module is Installed 7.4.2. Create a Channel Bonding Interface 7.4.3. Creating SLAVE Interfaces 7.4.4. Activating a Channel Bond 7.4.5. Creating Multiple Bonds 7.5. VERIFYING NETWORK CONFIGURATION BONDING FOR REDUNDANCY 7.6. OVERVIEW OF BONDING MODES AND THE REQUIRED SETTINGS ON THE SWITCH 7.7. USING CHANNEL BONDING 7.7.1. Bonding Module Directives 7.8. CREATING A BOND CONNECTION USING A GUI 7.8.1. Establishing a Bond Connection Saving Your New (or Modified) Connection and Making Further Configurations 7.8.1.1. Configuring the Bond Tab 7.9. ADDITIONAL RESOURCES Installed Documentation Online Documentation CHAPTER 8. CONFIGURE NETWORK TEAMING 8.1. UNDERSTANDING NETWORK TEAMING 8.2. UNDERSTANDING THE DEFAULT BEHAVIOR OF MASTER AND SLAVE INTERFACES 8.3. COMPARISON OF NETWORK TEAMING TO BONDING 8.4. UNDERSTANDING THE NETWORK TEAMING DAEMON AND THE "RUNNERS" 8.5. INSTALL THE NETWORK TEAMING DAEMON 8.6. CONVERTING A BOND TO A TEAM 8.7. SELECTING INTERFACES TO USE AS PORTS FOR A NETWORK TEAM 8.8. SELECTING NETWORK TEAM CONFIGURATION METHODS 8.9. CONFIGURE A NETWORK TEAM USING THE TEXT USER INTERFACE, NMTUI 8.10. CONFIGURE A NETWORK TEAM USING THE COMMAND LINE 8.10.1. Configure Network Teaming Using nmcli 8.10.2. Creating a Network Team Using teamd 8.10.3. Creating a Network Team Using ifcfg Files 8.10.4. Add a Port to a Network Team Using iputils 8.10.5. Listing the ports of a Team Using teamnl 8.10.6. Configuring Options of a Team Using teamnl 8.10.7. Add an Address to a Network Team Using iputils 8.10.8. open an Interface to a Network Team Using iputils 8.10.9. Viewing the Active Port Options of a Team Using teamnl 8.10.10. Setting the Active Port Options of a Team Using teamnl 8.11. CONTROLLING TEAMD WITH TEAMDCTL 8.11.1. Add a Port to a Network Team 8.11.2. Remove a Port From a Network Team 8.11.3. Apply a Configuration to a Port in a Network Team 8.11.4. View the Configuration of a Port in a Network Team 8.12. VERIFYING NETWORK CONFIGURATION TEAMING FOR REDUNDANCY 8.13. CONFIGURE TEAMD RUNNERS 8.13.1. Configure the broadcast Runner 8.13.2. Configure the random Runner 8.13.3. Configure the Round-robin Runner 8.13.4. Configure the activebackup Runner 8.13.5. Configure the loadbalance Runner 8.13.6. Configure the LACP (802.3ad) Runner 8.13.7. Configure Monitoring of the Link State 8.13.7.1. Configure Ethtool for link-state Monitoring 8.13.7.2. Configure ARP Ping for Link-state Monitoring 8.13.7.3. Configure IPv6 NA/NS for Link-state Monitoring 8.13.8. Configure Port Selection Override 8.13.9. Configure BPF-based Tx Port Selectors 8.14. CREATING A NETWORK TEAM USING A GUI 8.14.1. Establishing a Team Connection Saving Your New (or Modified) Connection and Making Further Configurations 8.14.1.1. Configuring the Team Tab 8.15. ADDITIONAL RESOURCES Installed Documentation Online Documentation CHAPTER 9. CONFIGURE NETWORK BRIDGING 9.1. CONFIGURE BRIDGING USING THE TEXT USER INTERFACE, NMTUI 9.2. USING THE NETWORKMANAGER COMMAND LINE TOOL, NMCLI 9.3. USING THE COMMAND LINE INTERFACE (CLI) 9.3.1. Check if Bridging Kernel Module is Installed 9.3.2. Create a Network Bridge 9.3.3. Network Bridge with Bond 9.4. CONFIGURE NETWORK BRIDGING USING A GUI 9.4.1. Establishing a Bridge Connection with a GUI Configuring the Connection Name, Auto-Connect Behavior, and Availability Settings 9.4.1.1. Configuring the Bridge Tab 9.5. ETHERNET BRIDGE CONFIGURATION USING IPROUTE 9.6. ADDITIONAL RESOURCES CHAPTER 10. CONFIGURE 802.1Q VLAN TAGGING 10.1. SELECTING VLAN INTERFACE CONFIGURATION METHODS 10.2. CONFIGURE 802.1Q VLAN TAGGING USING THE TEXT USER INTERFACE, NMTUI 10.3. CONFIGURE 802.1Q VLAN TAGGING USING THE COMMAND LINE TOOL, NMCLI Assigning Addresses to VLAN Interfaces 10.4. CONFIGURE 802.1Q VLAN TAGGING USING THE COMMAND LINE 10.4.1. Setting Up 802.1Q VLAN Tagging Using ifcfg Files 10.4.2. Configure 802.1Q VLAN Tagging Using ip Commands 10.5. CONFIGURE 802.1Q VLAN TAGGING USING A GUI 10.5.1. Establishing a VLAN Connection Saving Your New (or Modified) Connection and Making Further Configurations 10.5.1.1. Configuring the VLAN Tab 10.6. VLAN ON BOND AND BRIDGE USING IP COMMANDS 10.7. VLAN ON BOND AND BRIDGE USING THE NETWORKMANAGER COMMAND LINE TOOL, NMCLI 10.8. CONFIGURING VLAN SWITCHPORT MODE 10.9. ADDITIONAL RESOURCES CHAPTER 11. CONSISTENT NETWORK DEVICE NAMING 11.1. NAMING SCHEMES HIERARCHY 11.2. UNDERSTANDING THE DEVICE RENAMING PROCEDURE 11.3. UNDERSTANDING THE PREDICTABLE NETWORK INTERFACE DEVICE NAMES 11.4. NAMING SCHEME FOR NETWORK DEVICES AVAILABLE FOR LINUX ON SYSTEM Z 11.5. NAMING SCHEME FOR VLAN INTERFACES 11.6. CONSISTENT NETWORK DEVICE NAMING USING BIOSDEVNAME 11.6.1. System Requirements 11.6.2. Enabling and Disabling the Feature 11.7. NOTES FOR ADMINISTRATORS 11.8. CONTROLLING THE SELECTION OF NETWORK DEVICE NAMES 11.9. DISABLING CONSISTENT NETWORK DEVICE NAMING 11.10. TROUBLESHOOTING NETWORK DEVICE NAMING 11.11. ADDITIONAL RESOURCES Installed Documentation Online Documentation CHAPTER 12. CONFIGURING POLICY-BASED ROUTING TO DEFINE ALTERNATIVE ROUTES 12.1. ROUTING TRAFFIC FROM A SPECIFIC SUBNET TO A DIFFERENT DEFAULT GATEWAY Prerequisites Procedure Verification Steps Troubleshooting Steps Additional Resources PART III. INFINIBAND AND RDMA NETWORKING CHAPTER 13. CONFIGURE INFINIBAND AND RDMA NETWORKS 13.1. UNDERSTANDING INFINIBAND AND RDMA TECHNOLOGIES Prerequisites 13.2. TRANSFERRING DATA USING ROCE Prerequisites 13.3. CONFIGURING SOFT-ROCE Prerequisites Removing an RXE device Verifying Connectivity of an RXE device 13.4. INFINIBAND AND RDMA RELATED SOFTWARE PACKAGES 13.5. CONFIGURING THE BASE RDMA SUBSYSTEM 13.5.1. Configuration of the rdma.conf file 13.5.2. Usage of 70-persistent-ipoib.rules 13.5.3. Relaxing memlock restrictions for users 13.5.4. Configuring Mellanox cards for Ethernet operation 13.5.5. Connecting to a Remote Linux SRP Target Connecting to a Remote Linux SRP Target: High-Level Overview 13.6. CONFIGURING THE SUBNET MANAGER 13.6.1. Determining Necessity 13.6.2. Configuring the opensm master configuration file 13.6.3. Configuring the opensm startup options 13.6.4. Creating a P_Key definition 13.6.5. Enabling opensm 13.7. TESTING EARLY INFINIBAND RDMA OPERATION 13.8. CONFIGURING IPOIB 13.8.1. Understanding the role of IPoIB 13.8.2. Understanding IPoIB communication modes 13.8.3. Understanding IPoIB hardware addresses 13.8.4. Understanding InfiniBand P_Key subnets 13.8.5. Configure InfiniBand Using the Text User Interface, nmtui 13.8.6. Configure IPoIB using the command-line tool, nmcli 13.8.7. Configure IPoIB Using the command line 13.8.8. Testing an RDMA network after IPoIB is configured 13.8.9. Configure IPoIB Using a GUI Saving Your New (or Modified) Connection and Making Further Configurations 13.8.9.1. Configuring the InfiniBand Tab 13.8.10. Additional Resources Installed Documentation Online Documentation PART IV. SERVERS CHAPTER 14. DHCP SERVERS 14.1. WHY USE DHCP? 14.2. CONFIGURING A DHCP SERVER 14.2.1. Configuration File 14.2.2. Lease Database 14.2.3. Starting and Stopping the Server 14.3. DHCP RELAY AGENT 14.3.1. Configure dhcrelay as a DHCPv4 and BOOTP relay agent 14.3.2. Configure dhcrelay as a DHCPv6 relay agent 14.4. CONFIGURING A MULTIHOMED DHCP SERVER 14.4.1. Host Configuration 14.5. DHCP FOR IPV6 (DHCPV6) 14.6. CONFIGURING THE RADVD DAEMON FOR IPV6 ROUTERS 14.7. COMPARISON OF DHCPV6 TO RADVD Manually Using the radvd Daemon Using the DHCPv6 Server 14.8. ADDITIONAL RESOURCES CHAPTER 15. DNS SERVERS 15.1. INTRODUCTION TO DNS 15.1.1. Name server Zones 15.1.2. Name server Types 15.1.3. BIND as a Name server 15.2. BIND 15.2.1. Empty Zones 15.2.2. Configuring the named Service 15.2.2.1. Installing BIND in a chroot Environment 15.2.2.2. Common Statement Types 15.2.2.3. Other Statement Types 15.2.2.4. Comment Tags 15.2.3. Editing Zone Files 15.2.3.1. Common Directives 15.2.3.2. Common Resource Records 15.2.3.3. Comment Tags 15.2.3.4. Example Usage 15.2.4. Using the rndc Utility 15.2.4.1. Configuring the Utility 15.2.4.2. Checking the Service Status 15.2.4.3. Reloading the Configuration and Zones 15.2.4.4. Updating Zone Keys 15.2.4.5. Enabling the DNSSEC Validation 15.2.4.6. Enabling the Query Logging 15.2.5. Using the dig Utility 15.2.5.1. Looking Up a Nameserver 15.2.5.2. Looking Up an IP Address 15.2.5.3. Looking Up a Host Name 15.2.6. Advanced Features of BIND 15.2.6.1. Multiple Views 15.2.6.2. Incremental Zone Transfers (IXFR) 15.2.6.3. Transaction SIGnatures (TSIG) 15.2.6.4. DNS Security Extensions (DNSSEC) 15.2.6.5. Internet Protocol version 6 (IPv6) 15.2.7. Common Mistakes to Avoid 15.2.8. Additional Resources 15.2.8.1. Installed Documentation 15.2.8.2. Online Resources CHAPTER 16. CONFIGURING THE SQUID CACHING PROXY SERVER 16.1. SETTING UP SQUID AS A CACHING PROXY WITHOUT AUTHENTICATION Prerequisites Procedure Verification Steps 16.2. SETTING UP SQUID AS A CACHING PROXY WITH LDAP AUTHENTICATION Prerequisites Procedure Verification Steps Troubleshooting Steps 16.3. SETTING UP SQUID AS A CACHING PROXY WITH KERBEROS AUTHENTICATION Prerequisites Procedure Verification Steps Troubleshooting Steps 16.4. CONFIGURING A DOMAIN BLACKLIST IN SQUID Prerequisites Procedure 16.5. CONFIGURING THE SQUID SERVICE TO LISTEN ON A SPECIFIC PORT OR IP ADDRESS Prerequisites Procedure 16.6. ADDITIONAL RESOURCES APPENDIX A. RED HAT CUSTOMER PORTAL LABS RELEVANT TO NETWORKING BRIDGE CONFIGURATION NETWORK BONDING HELPER PACKET CAPTURE SYNTAX GENERATOR APPENDIX B. REVISION HISTORY B.1. ACKNOWLEDGMENTS INDEX