Filter
Top Products
PowerConnect B-Series FCX Configuration Guide 815
53-1002266-01
Configuring IP parameters – Layer 3 Switches
26
To increase the maximum number of static ARP table entries you can configure on a Layer 3
Switch, enter commands such as the following at the global CONFIG level of the CLI.
PowerConnect(config)# system-max ip-static-arp 1000
PowerConnect(config)# write memory
PowerConnect(config)# end
PowerConnect# reload
NOTE
You must save the configuration to the startup-config file and reload the software after changing the
static ARP table size to place the change into effect.
Syntax: system-max ip-static-arp <num>
The <num> parameter indicates the maximum number of static ARP entries and can be within one
of the ranges shown in Table 148, depending on the software version running on the device.
Configuring forwarding parameters
The following configurable parameters control the forwarding behavior of Layer 3 Switches:
• Time-To-Live (TTL) threshold
• Forwarding of directed broadcasts
• Forwarding of source-routed packets
• Ones-based and zero-based broadcasts
All these parameters are global and thus affect all IP interfaces configured on the Layer 3 Switch.
To configure these parameters, use the procedures in the following sections.
Changing the TTL threshold
The TTL threshold prevents routing loops by specifying the maximum number of router hops an IP
packet originated by the Layer 3 Switch can travel through. Each device capable of forwarding IP
that receives the packet decrements (decreases) the packet TTL by one. If a device receives a
packet with a TTL of 1 and reduces the TTL to zero, the device drops the packet.
The default TTL is 64. You can change the TTL to a value from 1 through 255.
To modify the TTL threshold to 25, enter the following commands.
PowerConnect(config)# ip ttl 25
Syntax: ip ttl <1-255>
Enabling forwarding of directed broadcasts
A directed broadcast is an IP broadcast to all devices within a single directly-attached network or
subnet. A net-directed broadcast goes to all devices on a given network. A subnet-directed
broadcast goes to all devices within a given subnet.
TABLE 148 Static ARP entry support
Default maximum Configurable minimum Configurable maximum
PowerConnect B-Series FCX devices
512 512 6000