Disabled IPv6 DAD: aligned with SONiC

[nazariig]

Signed-off-by: Nazarii Hnydyn nazariig@mellanox.com

Description of PR

Aligned IPv6 DAD with SONiC:
https://github.com/Azure/sonic-buildimage/blob/master/build_debian.sh

set /files/etc/sysctl.conf/net.ipv6.conf.default.accept_dad 0
set /files/etc/sysctl.conf/net.ipv6.conf.all.accept_dad 0
set /files/etc/sysctl.conf/net.ipv6.conf.eth0.accept_dad 0

Type of change

• [] Bug fix
• Testbed and Framework(new/improvement)
• [] Test case(new/improvement)

Approach

How did you do it?

• Added new rc.eos config file

How did you verify/test it?

1. Checked sysctl settings

bash-4.1# sysctl -q net.ipv6.conf | grep po1
net.ipv6.conf.po1.accept_dad = 0
net.ipv6.conf.po1.accept_ra = 0
net.ipv6.conf.po1.accept_ra_defrtr = 0
net.ipv6.conf.po1.accept_ra_pinfo = 0
net.ipv6.conf.po1.accept_redirects = 0
net.ipv6.conf.po1.accept_source_route = 0
net.ipv6.conf.po1.autoconf = 0
net.ipv6.conf.po1.dad_transmits = 1
net.ipv6.conf.po1.disable_ipv6 = 0
net.ipv6.conf.po1.force_mld_version = 0
net.ipv6.conf.po1.force_tllao = 0
net.ipv6.conf.po1.forwarding = 1
net.ipv6.conf.po1.hop_limit = 64
net.ipv6.conf.po1.max_addresses = 16
net.ipv6.conf.po1.mc_forwarding = 0
net.ipv6.conf.po1.mtu = 1500
net.ipv6.conf.po1.proxy_ndp = 0
net.ipv6.conf.po1.router_solicitation_delay = 1
net.ipv6.conf.po1.router_solicitation_interval = 4
net.ipv6.conf.po1.router_solicitations = 0

Any platform specific information?

• N/A

Supported testbed topology if it's a new test case?

• N/A

Documentation

• N/A

[pavel-shirshov]

But is it possible to disable ipv6 nd dad using command line?
Cisco has ipv6 nd dad attempts. I've found nothing for Arista.

[nazariig]

But is it possible to disable ipv6 nd dad using command line?
Cisco has ipv6 nd dad attempts. I've found nothing for Arista.

@pavel-shirshov Unfortunately i did not find such a way:

ARISTA01T2(config-if-Po1)#ipv6 nd ?
  cache                Cache entry
  managed-config-flag  set the 'managed address configuration flag' in IPv6 router advertisements
  ns-interval          Set advertised NS retransmission interval
  other-config-flag    set the 'other stateful configuration' flag in IPv6 router advertisements
  prefix               configure prefixes to be included in router advertisements on this interface.
  ra                   Router Advertisement commands
  reachable-time       configure reachable time - the amount of time that a remote IPv6 node is considered reachable
  router-preference    configure default router preference for the router on this interface ( Default: medium )

We can only check the feature status:

ARISTA01T2(config-if-Po1)#show ipv6 interface port-Channel 1
Port-Channel1 is up, line protocol is up (connected)
  IPv6 is enabled, link-local is fe80::5054:ff:fe7c:d35a/64
  Global unicast address(es):
    fc00::2, subnet is fc00::/126
  Joined group address(es):
    ff02::1
    ff02::1:ff00:2
    ff02::2
    ff02::1:ff7c:d35a
  ND DAD is enabled, number of DAD attempts: 1
  ND Reachable time is 2147483000 milliseconds
  ND retransmit interval is 1000 milliseconds
  ND advertised reachable time is 1 milliseconds (using 1)
  ND advertised retransmit interval is 0 milliseconds (unspecified)
  ND router advertisements are sent every 200 seconds
  ND router advertisements live for 1800 seconds
  ND advertised default router preference is Medium
  ND advertised maximum hop count limit is 64
  Hosts use stateless autoconfig for addresses.
  ND RAs are suppressed