Configure IP Routing Features Globally

About this task

Configure the IP routing protocol stack to determine which routing features the switch can use.

Procedure

  1. In the navigation tree, expand the following folders: Configuration > IP.
  2. Select IP.
  3. Select the Globals tab.
  4. To globally enable routing, select Forwarding.
  5. To globally configure the default TTL parameter type a value in the DefaultTTL field.

    This value is placed into routed packets that have no TTL specified.

  6. To globally enable IPv4 ICMP broadcast, select IcmpEchoBroadcastRequestEnable.
  7. To globally enable IPv4 Fragmented ICMP packet filtering, select IcmpDropFragmentsEnable.
  8. To globally enable the Alternative Route feature, select AlternativeEnable.
  9. To globally enable ICMP Router Discovery, select RouteDiscoveryEnable.
  10. To globally enable IP Sorce Routing, select SourceRouteEnable.
  11. To globally enable ECMP, select EcmpEnable.
  12. Configure the remaining parameters as required.
  13. Select Apply.

Globals Field Descriptions

Use the data in the following table to use the Globals tab.

Name

Description

Forwarding

Configures the system for forwarding (routing) or for dropping. The default value is forwarding.

DefaultTTL

Configures the default time-to-live (TTL) value for a routed packet. TTL indicates the maximum number of seconds elapsed before a packet is discarded. Enter an integer from 1 to 255. The default value of 255 is used if a value is not supplied in the datagram header.

ReasmTimeout

Specifies the maximum number of seconds that received fragments are held while they wait for reassembly. The default value is 30 seconds.

ICMPUnreachableMsgEnable

Enables the generation of Internet Control Message Protocol (ICMP) network unreachable messages if the destination network is not reachable from this system. These messages help determine if the system is reachable over the network. The default is disabled.

Important:

As a best pactice, enable icmp-unreach-msg only if it is absolutely required. If icmp-unreach-msg is enabled and a packet is received for which there is no route in the routing table, CPU utilization can dramatically increase.

ICMPRedirectMsgEnable

Enables or disables the system sending ICMP destination redirect messages.

IcmpEchoBroadcastRequestEnable

Enables or disables IP ICMP echo broadcast request feature. The default is enabled.

IcmpDropFragmentsEnable

Enables or disables IPv4 Fragmented ICMP packet filtering globally. The default is disabled.

AlternativeEnable

Globally enables or disables the Alternative Route feature.

If the alternative-route parameter is disabled, all existing alternative routes are removed. After the parameter is enabled, all alternative routes are re-added. The default is enabled.

RouteDiscoveryEnable

Enables the ICMP Router Discovery feature. The default is disabled (not selected). Use ICMP Router Discovery to enable hosts attached to multicast or broadcast networks to discover the IP addresses of neighboring routers.

AllowMoreSpecificNonLocalRouteEnable

Enables or disables a more-specific nonlocal route. If enabled, the system can enter a more-specific nonlocal route into the routing table. The default is disabled.

SuperNetEnable

Enables or disables supernetting.

If supernetting is globally enabled, the system can learn routes with a route mask less than 8 bits. Routes with a mask length less than 8 bits cannot have ECMP paths, even if you globally enable the ECMP feature. The default is disabled.

UdpCheckSumEnable

Enables or disables the UDP checksum calculation. The default is enable.

SourceRouteEnable

Enables or disables IP Source Routing globally. It is disabled by default.

ARPLifeTime

Specifies the lifetime of an ARP entry within the system, global to the switch. The default value is 360 minutes.

EcmpEnable

Globally enables or disables the Equal Cost Multipath (ECMP) feature. The default is disabled.

After ECMP is disabled, the EcmpMaxPath is reset to the default value of 1.

EcmpMaxPath

Globally configures the maximum number of ECMP paths.

You cannot configure this feature unless ECMP is enabled globally.

Different hardware platforms can support a different number of ECMP paths. For more information, see Fabric Engine Release Notes.

Ecmp1PathList

Selects a preconfigured ECMP path.

Ecmp2PathList

Selects a preconfigured ECMP path.

Ecmp3PathList

Selects a preconfigured ECMP path.

Ecmp4PathList

Selects a preconfigured ECMP path.

Ecmp5PathList

Selects a preconfigured ECMP path.

Ecmp6PathList

Selects a preconfigured ECMP path.

Ecmp7PathList

Selects a preconfigured ECMP path.

Ecmp8PathList

Selects a preconfigured ECMP path.

EcmpPathListApply

Applies changes in the ECMP pathlist configuration, or in the prefix lists configured as the pathlists.

TcpAdjustMssEnable

Adjusts the TCP maximum segment size (MSS) to improve the throughput for the TCP session over a Fabric Extend (FE) adjacency.

The default is disabled.

TcpAdjustMssStatus

Displays the activation status of the MSS adjustment functionality.

TcpAdjustMssType

Displays if the MSS adjustment value is manually configured or auto-derived.

The software does not support auto-derived values for this feature.

TcpAdjustMssValue

Configures the MSS adjustment value.

  • The default value is 1300.
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