IPv6 - Check whether IPv6 is disabled

This combiner reports whether the user has disabled IPv6 via one of the many means available to do so. At present, only whether IPv6 is disabled on the running system is reported; it provides no information regarding whether it would continue to be after a reboot.

Per https://access.redhat.com/solutions/8709 , IPv6 may be disabled by

RHEL 7:

• ipv6.disable=1 Kernel command line argument

• disable_ipv6 option in sysctl

RHEL 6:

• option ipv6 disable=1 in modprobe.d

• install ipv6 /bin/true (fake install) in modprobe.d

• disable_ipv6 option in sysctl

While they aren’t tested explicitly, there are some means by which you can attempt to disable IPv6 that are ineffective, such as setting blacklist ipv6 in modprobe.d; those methods will yield no result from this combiner.

The only requirement of this combiner is Uname, but accurate detection relies on information from combiners marked optional. If, for example, it’s run against a RHEL6 system without information from ModProbe, it will miss any of those disabling options and possibly return a false negative. For that reason, this combiner shouldn’t be relied on to state definitively that IPv6 is enabled or disabled.

Examples

>>> from insights.tests import context_wrap
>>> from insights.parsers.uname import Uname
>>> from insights.parsers.sysctl import Sysctl
>>> from insights.combiners.ipv6 import IPv6
>>> my_uname = '''
...  Linux localhost.localdomain 3.10.0-514.10.2.el7.x86_64 #1 SMP Mon Feb 20 02:37:52 EST 2017 x86_64 x86_64 x86_64 GNU/Linux
... '''.strip()
>>> my_sysctl = '''
... net.ipv6.conf.all.autoconf = 1
... net.ipv6.conf.all.dad_transmits = 1
... net.ipv6.conf.all.disable_ipv6 = 0
... net.ipv6.conf.all.force_mld_version = 0
... net.ipv6.conf.all.force_tllao = 0
... net.ipv6.conf.all.forwarding = 0
... '''.strip()
>>> shared = {Uname: Uname(context_wrap(my_uname)), Sysctl: Sysctl(context_wrap(my_sysctl))}
>>> my_ipv6 = IPv6({},shared)
>>> my_ipv6.disabled()
False
>>> my_ipv6.disabled_by()
set([])
>>> my_sysctl = '''
... net.ipv6.conf.all.autoconf = 1
... net.ipv6.conf.all.dad_transmits = 1
... net.ipv6.conf.all.disable_ipv6 = 1
... net.ipv6.conf.all.force_mld_version = 0
... net.ipv6.conf.all.force_tllao = 0
... net.ipv6.conf.all.forwarding = 0
... '''.strip()
>>> shared[Sysctl] = Sysctl(context_wrap(my_sysctl))
>>> my_ipv6 = IPv6({},shared)
>>> my_ipv6.disabled()
True
>>> my_ipv6.disabled_by()
set(['sysctl'])

class insights.combiners.ipv6.IPv6(uname, mod_probe, lsmod, cmdline, sysctl)

Bases: object

A combiner which detects disabled IPv6 networking.

disabled()

Determine whether IPv6 has been disabled on this system.

Returns:

True if a configuration that disables IPv6 was found.

Return type:

bool

disabled_by()

Get the means by which IPv6 was disabled on this system.

Returns:

Zero or more of cmdline, modprobe_disable, fake_install, or sysctl, depending on which methods to disable IPv6 have been found.

Return type:

set