Versions this guide is based on:

Type EVE Image Name Version vRAM
L2 L2-ADVENTERPRISEK9-M-15.1-20130726.bin I86BI_LINUXL2-ADVENTERPRISEK9-M 15.1(20130726:213425) 192

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.