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Cisco 3900 Series, Cisco 2900 Series, and Cisco 1900 Series Integrated Services Routers Generation 2 Software Configuration Guide
Chapter Basic Router Configuration
Configuring I/O Memory Allocation
For complete information on global parameter commands, see the Cisco IOS Release configuration
guide documentation set.
Configuring I/O Memory Allocation
To reallocate the percentage of DRAM in use for I/O memory and processor memory on Cisco 3925E
and Cisco 3945E routers, use the
memory-size iomem
i/o-memory-percentage
command in global
configuration mode. To revert to the default memory allocation, use the
no
form of this command. This
procedure enables
smartinit
.
Tip
We recommend that you configure the memory-size iomem below 25%. Any value above 25% should be
used only for enhancing IPSec performance.
When you specify the percentage of I/O memory in the command line, the processor memory
automatically acquires the remaining percentage of DRAM memory.
Example
The following example allocates 25% of the DRAM memory to I/O memory and the remaining 75% to
processor memory:
Router#config t
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)# memory-size iomem 5
IO memory size too small: minimum IO memory size is 201M
Router(config)#
Router(config)# memory-size iomem ?
<5-50> percentage of DRAM to use for I/O memory: 5, 10, 15, 20, 25, 30, 40, 50
Router(config)#
memory-size iomem 25
Smart-init will be disabled and new I/O memory size will take effect upon reload.
Router(config)# end
Step 3
enable secret
password
Example:
Router(config)# enable secret cr1ny5ho
Router(config)#
Specifies an encrypted password to prevent
unauthorized access to the router.
Step 4
no ip domain-lookup
Example:
Router(config)# no ip domain-lookup
Router(config)#
Disables the router from translating unfamiliar
words (typos) into IP addresses.
Command
Purpose
Syntax Description
i/o-memory-percentage
The percentage of DRAM allocated to I/O memory. The values permitted
are 5, 10, 15, 20, 25, 30, 40, and 50. A minimum of 201 MB of memory is
required for I/O memory.