Enabling & Disabling Promiscuous mode on Ethernet


                     You can try below things to get it done;

In RHEL / CentOS :

#/sbin/ifconfig ethX promisc   (Temporary solution, You will loose setting if you reboot VM )

To set it permanently Edit file –

#cat /etc/sysconfig/network-scripts/ifcfg-eth1

BOOTPROTO=static
DEVICE=eth1
TYPE=Ethernet
PROMISC=yes
USERCTL=no
PEERDNS=no
HWADDR=xx:xx:xx:C8:67:0E


In SLES :

Temporary solution is same as above.

But for permanent change edit file “ /etc/sysconfig/network/ifcfg-rth-id-xx:xx:xx:xx:xx:xx”

Here you can add line “ifconfig eth0 promisc” OR if this doesn’t work add “PROMISC=yes”


And to disable this mode either simply remove added line from the respective files or use command ;

#/sbin/ifconfig ethX -promisc   (Temporary solution)

Comments

  1. AnonymousJanuary 29, 2015 at 8:58 PM

    Thanks for this info. It was very useful. I was frustrated trying to find info in the SUSE manuals regarding promisc mode. No info supplied at all. And the logical solution of adding PROMISC='yes' to the ifcfg-eth1 file (with or without quotes) failed. The final solution to permanently (meaning after a reboot) add promisc mode was to add, ifconfig eth1 promisc , to the ifcfg-eth1 file.

    ReplyDelete
  2. Amy CJune 20, 2022 at 8:14 AM

    Thaanks great blog

    ReplyDelete

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