Cisco IOL (IOS on Linux)

This guide is based on:

Recommended IOL image versions:

Note: The older IOL versions might not work. Avoid using IOL L3 15.5.2T (it has serious freeze console bug after some time of running)

Type EVE Image Name Version NVRAM RAM
L2/L3 Switch i86bi_linux_l2-adventerprisek9-ms.SSA.high_iron_20190423.bin Cisco IOS Software, Linux Software (I86BI_LINUXL2-ADVENTERPRISEK9-M), Version 15.2(CML_NIGHTLY_20190423) 1024 1024
L2/L3 Switch i86bi_LinuxL2-AdvEnterpriseK9-M_152_May_2018.bin Cisco IOS Software, Linux Software (I86BI_LINUXL2-ADVENTERPRISEK9-M), Version 15.2(CML_NIG HTLY_20180510)FLO_DSGS7 1024 1024
L3 router i86bi_LinuxL3-AdvEnterpriseK9-M2_157_3_May_2018.bin Cisco IOS Software, Linux Software (I86BI_LINUX-ADVENTERPRISEK9-M), Version 15.7(3)M2, Compiled Wed 28-Mar-18 11:18 by prod_rel_team 1024 1024
L3 Router i86bi_linux-adventerprisek9-ms.156-3.M3a.bin Cisco IOS Software, Linux Software (I86BI_LINUX-ADVENTERPRISEK9-M), Version 15.6(3)M3a, Compiled Tue 19-Sep-17 10:03 by prod_rel_team 1024 1024
L3 Router L3-ADVENTERPRISEK9-M-15.4-2T.bin Cisco IOS Software, Linux Software (I86BI_LINUX-ADVENTERPRISEK9-M), Version 15.4(2)T4, Compiled Thu 08-Oct-15 21:21 by prod_rel_team 1024 1024


Other versions should also be supported following bellow’s procedure.

IOL or IOS On Linux, also called IOU or IOS On Unix. IOL, is a simulator available for Cisco internal use only. IOL refers to the Linux version, compiled for i386 architecture. IOU refers to the Unix (Solaris) version compiled for Sparc architecture. The term IOU usually refers to IOL too.

Because IOL is an internal IOS version, IOL can be used by Cisco employees or by authorized customers only.

Upload the downloaded image to the EVE using for example FileZilla or WinSCP to:  /opt/unetlab/addons/iol/bin/.

Type following command to fix permissions:

/opt/unetlab/wrappers/unl_wrapper -a fixpermissions

IOL images must end with the “.bin” extension and must be executable. License must be stored under the same path.

IOU/IOL license is bound to the hostname and domain name of the server. A test should be made to check if IOU/IOL images can run properly.

Google for how to create iourc license file. Bellow is an EXAMPLE how it should look like:

cat /opt/unetlab/addons/iol/bin/iourc
unl01 = 0123456789abcdef;

Testing Cisco IOU/IOL Images:

cd /opt/unetlab/addons/iol/bin
touch NETMAP
LD_LIBRARY_PATH=/opt/unetlab/addons/iol/lib /opt/unetlab/addons/iol/bin/<iosname.bin> 1

IOS On Unix - Cisco Systems confidential, internal use only
Under no circumstances is this software to be provided to any
non Cisco staff or customers.  To do so is likely to result
in disciplinary action. Please refer to the IOU Usage policy at for more information.

              Restricted Rights Legend

Use, duplication, or disclosure by the Government is
subject to restrictions as set forth in subparagraph
(c) of the Commercial Computer Software - Restricted
Rights clause at FAR sec. 52.227-19 and subparagraph
(c) (1) (ii) of the Rights in Technical Data and Computer
Software clause at DFARS sec. 252.227-7013.

           cisco Systems, Inc.
           170 West Tasman Drive
           San Jose, California 95134-1706

If the IOL/IOU instance doesn’t start, then you won’t be able to use IOL/IOU nodes inside EVE.