On 11/19/18 6:49 AM, Simon Matter wrote:
On 11/17/18 8:31 AM, Alice Wonder wrote:
On 11/17/2018 07:01 AM, Alice Wonder wrote:
On 11/17/2018 06:43 AM, Alice Wonder wrote:
CentOS 7.5 image running on linode.
unbound running on localhost.
Have to use a cron job once a minute to keep /etc/resolv.conf using
the localhost for name resolution - whenever NetworkManager gets
restarted (usually only a system boot) it gets over-written.
It seems every distro has a different way of preventing
NetworkManager from replacing that file.
I found instructions for Fedora that said create
/etc/NetworkManager/conf.d/no-dns.conf containing
[main]
dns=none
That doesn't seem to have any effect.
Poking around, I find a file on boot seems to be created called
/var/run/NetworkManager/resolv.conf
It has most of the contents of what ends up in /etc/resolv.conf -
except w/o the last line, which just reads rotate in generated
/etc/resolv.conf.
It says it's generated by NetworkManager (both /etc/resolv.conf and
the one in /var/run/NetworkManager) but neither are specific enough
to indicate what is causing them to be created so I can turn it off.
Anyone know how to tell NetworkManager to just not create that file?
Using a cron job to overwrite it once a minute works but there must
be a proper way.
I really wish KISS was a design goal when designing system
configuration.
_______________________________________________
CentOS mailing list
CentOS@xxxxxxxxxx
https://lists.centos.org/mailman/listinfo/centos
Just found this -
# cat dhclient-exit-hooks
echo 'options rotate' >> /etc/resolv.conf
That's where the last line in /etc/resolv.conf is coming from.
Okay replacing the contents of dhclient-exit-hooks with
echo -e 'nameserver 127.0.0.1\nnameserver ::1' > /etc/resolv.conf
seems to do what I need.
I hope RHEL/CentOS 8 do networking better, as in, not have spaghetti
scripts called here and there making something that should be a config
option hard to do.
With DNS the only way to trust results is if the zone is signed and
local resolver validates. You can't ever trust external nameservers
defined by dhcp to validate. So there's very valid reasons to want to
use local unbound.
_______________________________________________
I don't know about CentOS 7 because I'm running CentOS 6, but on other
systemd distributions where I've run into similar issues I was either
able to add a hardcoded DNS server to network manager or resolve the
problem through systemd-resolved.
In one case I resolved the issue best by disabling systemd-resolved, but
if you check the man page for systemd-resolved as wells as the man page
for resolved.conf (/etc/systemd/resolved.conf on other distributions)
my sense is you will find a cleaner solution. It would seem to me that
if you are running bind or powerdns on your local host, then it would
make sense to me to disable systemd-resolved, since you don't need so
many layers of caching dns resolvers.
Alice was talking about CentOS 7.5, which doesn't have systemd-resolved
nor does it have systemd-networkd. I didn't look at EL8 betas yet but we
can probably expect systemd-networkd to be included there. If that's the
case, we'll probably have legacy script based configs, NetworkManager and
systemd-networkd/systemd-resolved.
In other words, things may not get easier in the future but even more
confusing. At least that's already the case if you run different
distributions.
Regards,
Simon
_______________________________________________
CentOS mailing list
CentOS@xxxxxxxxxx
https://lists.centos.org/mailman/listinfo/centos
Hi
in august 1017 i had put away the following remark about this item:
#edit
gvim /var/run/NetworkManager/resolv.conf
# to your needs
# make /etc/resolv.conf a link to the above file
rm /etc/resolv.conf
ln -s /lib/systemd/resolv.conf /etc/resolv.conf
# dns=none does not work in either /etc/NetworkManager/NetworkManager.conf
# nor in /etc/NetworkManager/conf.d/dns.conf
-------------------
OR, much simpler:
in /etc/sysconfig/network-scripts/ifcfg-ethX
....
PEERDNS=no
IPV6_PEERDNS=no
....
suomi
_______________________________________________
CentOS mailing list
CentOS@xxxxxxxxxx
https://lists.centos.org/mailman/listinfo/centos
