4 Replies Latest reply: Aug 10, 2018 12:21 PM by Juergen Ilse CCNA R&S RSS

    Back to the basics: Cisco device Memories


      Hello all,


      Below paragraphs are from ICND1 OCG page 835.

      Can you tell me why there are two numbers in "483328K/40960K bytes of memory"?

      Here is my understanding.

      The 483328K/40960K bytes of memory is used for calculation. It says it's DRAM. Would newer Cisco devices use faster DDR3 or DDR4 RAM?

      The 255K NVRAM is used for storing files only.

      The 3425968K bytes of USB Flash usbflash1 (Read/Write) and 250880K bytes of ATA System CompactFlash 0 (Read/Write) are just extra file storage in the form of USB stick and CompactFlash if needed.


      Is that correct?


      page 835, ICND1 OCG:


      To help point out some of the many important facts in this command, the example shows

      many highlighted items. The following list describes each of the items in the output in the

      same order as they are shown in the example, top to bottom:


      1. The IOS version

      2. The uptime (the length of time that has passed since the last reload)

      3. The reason for the last reload of IOS ( reload command, power off/on, software


      4. The time of the last loading of IOS (if the router’s clock has been set)

      5. The source from which the router loaded the current IOS

      6. The amount of RAM memory

      7. The number and types of interfaces

      8. The amount of NVRAM memory

      9. The amount of flash memory

      10. The configuration register’s current and future setting (if different)



      Cisco CISCO2901/K9 (revision 1.0) with 483328K/40960K bytes of memory.

      Processor board ID FTX1628837T

      2 Gigabit Ethernet interfaces

      4 Serial(sync/async) interfaces

      1 terminal line

      DRAM configuration is 64 bits wide with parity enabled.

      255K bytes of non-volatile configuration memory.

      3425968K bytes of USB Flash usbflash1 (Read/Write)

      250880K bytes of ATA System CompactFlash 0 (Read/Write)