This section provides information to configure an IP router.
Topics in this section include:
On a 7705 SAR, an interface is a logical named entity. An interface is created by specifying an interface name under the config>router context, the global router configuration context where objects like static routes and dynamic routing are defined. An IP interface name can be up to 32 alphanumeric characters, must start with a letter, and is case-sensitive; for example, the interface name “1.1.1.1” is not allowed, but “int-1.1.1.1” is allowed.
To create an interface on an Alcatel-Lucent 7705 SAR, the basic configuration tasks that must be performed are:
A system interface and network interface should both be configured unless the network interface is configured as an unnumbered interface. In that case, the network interface borrows (or links to) an IP address from another interface on the system (the system IP address, another loopback interface, or any other numbered interface), which serves as a combined system IP address and network IP address.
A system interface is a virtual interface similar to other interfaces but with only some operational parameters. The IP address, shutdown and no shutdown attributes are the only operational parameters for the system interface.
The system interface must have an IP address with a 32-bit subnet mask. The system interface is associated with the node (such as a specific 7705 SAR), not a specific interface. The system interface is also referred to as the loopback interface. The system interface is associated during the configuration of the following entities:
The system interface is used to preserve connectivity (when alternate routes exist) and to decouple physical connectivity and reachability. If an interface carrying peering traffic fails, and there are alternative routes to the same peer system interface, peering could be either unaffected or re-established over the alternate routes. The system interface IP address is also used for pseudowire/VLL signaling (via targeted LDP).
The system interface is used as the router identifier if a router ID has not been explicitly configured.
A network interface can be configured on a physical or logical port.
On the 2-port 10GigE (Ethernet) Adapter card/module, the network interface can only be created on the v-port (not the ring ports).
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Refer to Filter Policies and Route Policies for information on configuring these policies. |
The most basic router configuration must have the following:
The following example displays a router configuration.
The following sections describe basic system tasks:
Use the system command to configure a name for the device. The name is used in the prompt string. Only one system name can be configured. If multiple system names are configured, the last one configured will overwrite the previous entry.
If special characters are included in the system name string, such as spaces, #, or ?, the entire string must be enclosed within double quotes.
Use the following CLI syntax to configure the system name:
The following example displays the system name output.
Use the following CLI syntax to configure IPv6 neighbor discovery parameters:
The following example displays IPv6 neighbor discovery parameters output.
The following command sequences create a system interface and a logical IP interface. The system interface assigns an IP address to the interface, and then associates the IP interface with a physical port. The logical interface can associate attributes like an IP address or port.
The system interface cannot be deleted.
Use the following CLI syntax to configure a system interface:
On the 2-port 10GigE (Ethernet) Adapter card/module, a network address is assigned to the v-port only.
Use the following CLI syntax to configure a network interface:
The preceding syntax example shows a configuration where the address is entered manually. To have the interface enabled for dynamic address assignment, use the dhcp keyword and, optionally, assign client ID and vendor class ID.
In addition, to apply and configure a per-VLAN network egress aggregate shaper, use the queue-policy and agg-rate-limit commands.
The following example displays the IP configuration output showing the interface information.
When configuring an IPv6 interface, a link-local address (FE80::x:x:x:x:x:x:x/64) is automatically generated after the CLI command ipv6 is given. If the port is already assigned to the interface when IPv6 is enabled, the link-local address is derived from the port MAC address. Otherwise, the link-local address is derived from the system MAC address.
In either case, if the configuration file is saved and the node is rebooted, the port will be assigned to the interface before IPv6 is enabled and the link-local address will be derived from the port MAC address. This means that the link-local address will change after the node is rebooted if it was derived from the system MAC address before the reboot.
To avoid having the link-local address change after a reboot, IPv6 on the interface should be configured in the following order. This will ensure that the link-local address is derived from the port MAC address and will therefore not change after a reboot.
Use the following CLI syntax to configure an unnumbered interface:
The preceding syntax example shows a configuration where the address is entered manually. To have the interface enabled for dynamic assignment of the system IP address, use the dhcp keyword and, optionally, assign client ID and vendor class ID.
IP version 6 (IPv6) addresses are supported on:
Use the following CLI syntax to configure IPv6 parameters:
To configure the router to originate router advertisement messages, the router-advertisement command must be enabled. All other router advertisement configuration parameters are optional. Router advertisement on all IPv6-enabled interfaces will be enabled.
Use the following CLI syntax to enable router advertisement and configure router advertisement parameters:
The following example displays a router advertisement configuration:
ECMP (Equal-Cost Multipath Protocol) refers to the distribution of packets over two or more outgoing links that share the same routing cost. The 7705 SAR load-balances traffic over multiple equal-cost links with a hashing algorithm that uses header fields from incoming packets to calculate which link to use. By adding additional fields to the algorithm, you can increase the randomness of the results and ensure a more even distribution of packets across available links. ECMP is supported on static routes and dynamic (OSPF, IS-IS, and BGP) routes. The 7705 SAR supports ECMP for LDP and IP traffic.
If multiple routes are learned with an identical preference using the same protocol, the lowest-cost route is used. If multiple routes are learned with an identical preference using the same protocol and the costs (metrics) are equal, the decision of which route to use is determined by the configuration of ECMP in the config>router context.
Use the following CLI syntax to configure ECMP, enable it and specify the maximum number of routes to be used for route sharing (up to 8):
The 7705 SAR supports both static routes and dynamic routing to next-hop addresses.
For information on configuring OSPF, RIP, IS-IS, and BGP routing, refer to the 7705 SAR OS Routing Protocols Guide.
Only one next-hop IP address can be specified per IP interface for static routes.
Use the following CLI syntax to create static route entries:
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If ldp-sync is enabled on a static route, the ldp synchronization timer must also be configured on the associated interface, using the config>router>if>ldp-sync-timer command. |
The router ID defaults to the address specified in the system interface command. If the system interface is not configured with an IP address, the router ID inherits the last 4 bytes of the MAC address. Alternatively, the router ID can be explicitly configured with the config>router>router-id command.
When configuring a new router ID, protocols are not automatically restarted with the new router ID. The next time a protocol is initialized, the new router ID is used. To force the new router ID, issue the shutdown and no shutdown commands for OSPF, IS-IS, or BGP, or restart the entire router.
Use the following CLI syntax to configure a router ID:
The following example displays a router ID configuration:
Configuring an autonomous system is optional.
Use the following CLI syntax to configure an autonomous system:
The following displays an autonomous system configuration example:
Use the following CLI syntax to configure ICMP for the router:
The number and seconds parameters represent how many of each of these types of ICMP errors the node will generate in the specified interval on the specified interface.
Use the following CLI syntax to configure ICMPv6 for the router:
The number and seconds parameters represent how many of each of these types of ICMPv6 errors the node will generate in the specified interval on the specified interface.
Use the following CLI syntax to configure the router as a DHCP Relay agent:
The following example displays the router DHCP Relay agent creation output.
To configure proxy ARP, you must first:
The following example displays the proxy ARP configuration output.
For more information on route policies, see Route Policies.
Apply the policy statement to the proxy ARP policy in the config>router>if> proxy-arp-policy context.
The following example displays the router interface proxy ARP configuration.
To configure NAT or firewall security functionality, you must:
The following example displays a NAT zone configuration output.
The 7705 SAR supports rule-based logging (that is, logging for each entry of a security policy) and zone-based logging.
Logging is suppressed by default. To enable either rule-based logging or zone-based logging, logging must be configured as part of the security policy configuration.
If a packet does not match any of the rules in a security policy, the packet is dropped from a security session because the default security policy action is to reject non-matching packets. With rule-based logging, in order to see that event in the event log, the policy must be configured with a rule to log rejected, non-matching packets to the log-id, and this rule must be configured as the last entry in the policy.
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If the policy>entry>logging to log-id command is enabled, the zone>log command cannot be enabled because a log-id cannot be configured at both the policy and zone levels. |
Use the following CLI syntax to configure rule-based security logging:
The following example displays a rule-based logging configuration output.
The following example displays the error that occurs when there is an attempt to configure a log-id at both the policy level and the zone level.
Zone-based logging is enabled when the config>security>policy> entry>logging to zone command is configured as part of the security policy configuration. Zone-based logging can be configured after the policy has been created, but this requires the begin and commit actions, which cause existing security sessions to be cleared.
Use the following CLI syntax to configure zone-based security logging:
The following example displays a zone-based logging configuration output.
The following example displays a zone-based logging configuration output for a VPRN service.
Use the following CLI syntax to apply an application group or a host group to a security policy:
The following output is an example of applying an application group and a host group to a security policy:
This section discusses the following service management tasks:
The system command sets the name of the device and is used in the prompt string. Only one system name can be configured. If multiple system names are configured, the last one configured will overwrite the previous entry.
Use the following CLI syntax to change the system name:
The following example displays the system name change.
Starting at the config>router level, navigate down to the router interface context.
To modify an IP address, perform the following steps:
To modify a port, perform the following steps:
The following example displays the interface configuration.
The no form of the interface command typically removes the entry, but all entity associations must be shut down and/or deleted before an interface can be deleted.