Roger Perkin

Learn Network Automation

cisco 3850 ios upgrade

Do you want to perform a Cisco 3850 IOS Upgrade?

This short post will show you how to upgrade the software on a single Cisco 3850 switch or a 3850 stack, using TFTP and USB.

The Cisco 3850 IOS upgrade procedure is very easy but it is a bit different than the usual software image of previous switches i.e 3750 etc.

The main difference is the Cisco 3850 switch run IOS-XE so you have to copy the .bin file to the flash on the switch and then install the software on the switch.

  1. Download the required image from cisco.com
  2. Begin the install
  3. Reboot the switch

Step 1 copy the new image to the 3850

3850-SW1#copy tftp flash
Address or name of remote host []? 10.1.1.250
Source filename []? cat3k_caa-universalk9.SPA.03.03.01.SE.150-1.EZ1.bin
Destination filename [cat3k_caa-universalk9.SPA.03.03.01.SE.150-1.EZ1.bin]?
Accessing tftp://10.1.1.250/cat3k_caa-universalk9.SPA.03.03.01.SE.150-1.EZ1.bin…
Loading cat3k_caa-universalk9.SPA.03.03.01.SE.150-1.EZ1.bin from 10.251.226.253 (via Port-channel1): !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Once the file has been copied verify the new IOS is present in flash

3850-SW1#dir flash:

Directory of flash:/

46472  -rwx     2097152  Sep 22 2013 10:23:20 +00:00  nvram_config
46468  -rwx     1689445  Aug 22 2013 20:48:35 +00:00  asic_dump_reg-1.csv
46467  -rwx     1689445  Aug 22 2013 21:17:05 +00:00  asic_dump_reg-0.csv
46469  -rwx         114  Sep 13 2013 06:08:19 +00:00  express_setup.debug
46466  -rw-   223737704  Feb 12 12:01:30 +00:00  cat3k_caa-universalk9.SPA.03.03.01.SE.150-1.EX3.bin
38721  drwx        4096  Sep 22 2013 10:14:12 +00:00  mnt
77443  -rwx        1224  Sep 22 2013 10:13:17 +00:00  packages.conf
46470  -rwx         736  Sep 20 2013 18:34:18 +00:00  vlan.dat
69699  -rwx    74369252  Sep 22 2013 10:13:12 +00:00  cat3k_caa-base.SPA.03.02.02.SE.pkg
69700  -rwx     5808828  Sep 22 2013 10:13:12 +00:00  cat3k_caa-drivers.SPA.03.02.02.SE.pkg
69701  -rwx    32488292  Sep 22 2013 10:13:12 +00:00  cat3k_caa-infra.SPA.03.02.02.SE.pkg
69702  -rwx    30403764  Sep 22 2013 10:13:12 +00:00  cat3k_caa-iosd-universalk9.SPA.150-1.EX2.pkg
69703  -rwx    16079584  Sep 22 2013 10:13:12 +00:00  cat3k_caa-platform.SPA.03.02.02.SE.pkg
69704  -rwx    64580300  Sep 22 2013 10:13:13 +00:00  cat3k_caa-wcm.SPA.10.0.111.0.pkg

1621966848 bytes total (1123991552 bytes free)

Step 1a copy the software to the 3850 using USB

The image for the 3850 is very big 250Mb+ so copying via TFTP can take a while, a much better solution is to use a USB stick.

The process is very simple and much easier than using tftp. All you need is a USB stick that is recognised by the switch and a console connection.

I use a Kingston 16GB stick - http://www.amazon.co.uk/Kingston-Drive-Premium-Metal-Casing/dp/B005SP91UW

Copy the image file into the root of drive and insert the USB drive into the USB slot on the front of the 3850.

From the Command line verify that the switch can recognise the file system.

dir usbflash0:

This should list all the files on your USB

You now need to copy the image from the USB to the Flash of the switch.

copy usbflash0:cat3k_caa-universalk9.SPA.03.03.01.SE.150-1.EX3.bin flash:

Now proceed to the software install in Step 2

Step 2 start the install

3850-SW1#software install file flash:cat3k_caa-universalk9.SPA.03.03.01.SE.150-1.EX3.bin switch 1-2

Please note the switch 1-2 command at the end will install the image onto switch 1 and 2 in your stack, so if you are running a stack of 8 switches you need to enter switch 1-8

This step will unpack the .bin file and install the software, after the software has installed you will be promted to reboot, the switch will reload and you can then verify you are running the new IOS

3850-SW1#sh ver | i INSTALL
*    1 32    WS-C3850-24T       03.03.01SE        cat3k_caa-universalk9 INSTALL
2 32    WS-C3850-24T       03.03.01SE        cat3k_caa-universalk9 INSTALL

How do I update my Cisco 9300 switch stack?

Check my other post on how to upgrade a Nexus 9k here - https://www.rogerperkin.co.uk/cisco/software-upgrade-guides/nexus-9000-software-upgrade/

Can I upgrade my Cisco 3850 with USB?

Yes you can, the upgrade procedure detailed above covers both USB method and FTP method. I personally prefer USB method if I am on site with the equipment.

If you are interested in Network Automation check out my pages on Ansible & Python

For a more detailed guide to this process please check this Cisco Doc - here

Click here for more of my Software Upgrade Guides

How to upgrade IOS on Cisco 4500X Switch

How to upgrade Cisco IOS using Ansible

Official Cisco Documentation 

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Comments

  1. Roger, Thank you for describing the whole process in a netshell. I have question, when upgrading a stack do we need to copy the now IOS to every switch or copying it to Master will do the magic.

    Once again thank for your post, much appreciated!

    • Lateef,when upgrading the software on a stack, you only have to copy the software to one switch.

      Use the command

      Switch#software install file flash:cat3k_caa-universalk9.SPA.03.02.02.SE.150-1.EX2.bin switch 1-2

      Replace 1-2 with as many switches that you have in the stack, the entire stack will reboot and upgrade them all.

    • Jared, That is great news - I had spent a while looking for this information the first time I did a stack upgrade, hence the reason for the post, glad it helped.

  3. Hi Roger! when updating an stack (in my case 8 member stack) will it ask me to reboot each switch or it will just reboot all of them at the same time?

    We need to reboot each member one by one

    thanks!
    xavier

    • Xavier,

      As far as I am aware there is no way to reload each switch one by one - during an upgrade.

      As soon as you finish uploading the image the stack will reload.

  4. A couple of things you might add:
    use the “software clean” install to clean up old packages and free up space
    use the “verify /md5 filename hash” (where filename is the xe image and the hash is the one provided by Cisco) to ensure your image is clean and non-corrupt

    Great write-up.

  5. Hi, I followed this process and adter the install and after the switch rebooted, all I get is ssssssssssssssssssspssssssssssssssssssspssssssssssssssssssspssssssssss and has been going for a while with no end in site, do you know what the issue is?

      • Hi Sam

        I did this upgrade last night and he Sssssss is normal it is a part of the Upgrade just had to wait it ouT.

        Thanks so much flr the post rogers this was much more clear then cisco Doc. I have kne question how comfortable would you feel soing this upgrade remotley? I did this onsite last night but have more customers to upgrade

        • It depends on how big the upgrade is and how much code needs to be written, I have seen it upgrade in 5 minutes and other switches take 20 minutes - you have to be patient and don’t be afraid if it appears to be stuck, just reload the stack and try again.

          I would not be comfortable doing this process remotely without any remote hands.

          If you have out of band console and someone to power the stack if required then no problem.

  7. Hi ,

    Is it possible to do the Cisco 3850 stack Firmware upgrade without an outage .

    Regards

    Rengith Kumar RS

  8. Can the stack be broken and then upgrade and reboot each Switch indepenedtly? Then after upgrading the last stack member rejoin the whole stack?

  9. Hi Roger,

    I have 3 new 3850s out of the box new and I have a question on procedure.
    connectivity steps.
    1. rack each switch
    2. do I add power cables to power supplies next step and power on all 3 switches
    3. do I add power stack cable or stackwise cable next?
    4. should I connect power stack cable from top switch (1) to bottom switch (3) and then another cable from switch (1) to middle switch (2) and lastly the middle switch (2) to the bottom switch (3).
    once I have all of the cabling completed.
    1. do I enable auto-upgrade.
    2. do I configure the top switch as active with priority of 1.
    3. do I change the switch to install mode.
    4. do I install my usb with my IOS 3.6.6 into the top switch (1) and copy the bin file into flash.
    5. do I verify the new file in the flash dir?
    6. do I issue the reload command to have the switch reboot with the new ios.
    7. will only the top switch (1) reload or the entire stack.
    8. after the reload will the other (2) switches in the stack auto-upgrade to 3.6.6.

    please let me know as this is my first time installing a 3 switch stack.

  10. Dear Roger,
    If I have only one switch currently in stack so we can remove the keyword switch from the below :

    3850-SW1#software install file flash:cat3k_caa-universalk9.SPA.03.03.01.SE.150-1.EX3.bin

    Or this is wrong.

  11. had to use the following command:

    software install file flash-1:cat3k_caa-universalk9.16.03.07.SPA.bin new force switch 1-4

    new force to get past initial compatibility errors