• Jay Vosburgh's avatar
    bonding / ipv6: no addrconf for slaves separately from master · c2edacf8
    Jay Vosburgh authored
    	At present, when a device is enslaved to bonding, if ipv6 is
    active then addrconf will be initated on the slave (because it is closed
    then opened during the enslavement processing).  This causes DAD and RS
    packets to be sent from the slave.  These packets in turn can confuse
    switches that perform ipv6 snooping, causing them to incorrectly update
    their forwarding tables (if, e.g., the slave being added is an inactve
    backup that won't be used right away) and direct traffic away from the
    active slave to a backup slave (where the incoming packets will be
    dropped).
    
    	This patch alters the behavior so that addrconf will only run on
    the master device itself.  I believe this is logically correct, as it
    prevents slaves from having an IPv6 identity independent from the
    master.  This is consistent with the IPv4 behavior for bonding.
    
    	This is accomplished by (a) having bonding set IFF_SLAVE sooner
    in the enslavement processing than currently occurs (before open, not
    after), and (b) having ipv6 addrconf ignore UP and CHANGE events on
    slave devices.
    
    	The eql driver also uses the IFF_SLAVE flag.  I inspected eql,
    and I believe this change is reasonable for its usage of IFF_SLAVE, but
    I did not test it.
    Signed-off-by: default avatarJay Vosburgh <fubar@us.ibm.com>
    Signed-off-by: default avatarJeff Garzik <jeff@garzik.org>
    c2edacf8
bond_main.c 125 KB