CentOS - Oct 2020 - Unable to get dummy interfaces to persist across reboots in CentOS 8

Hello all, hoping someone can help me out here.

I cannot get dummy interfaces on a new Cent8 build to persist across reboots.

On Cent7 - this is the process I use:

Create Dummies:
# cat /etc/modules-load.d/dummy.conf
dummy
# cat /etc/modprobe.d/dummyopts.conf
options dummy numdummies=4
# ip link add dummy0 type dummy
## - repeating a/ ascending dummyN adapters for as many needed
# service network start
# dracut -f

Now  this  was  different than even how 6 handled it, forget how I
finally dug that up (possible I even asked here).  I've applied this
same configuration to a Cent8 box I'm trying to stand up and it all
appears to work fine, but unlike the Cent7 boxes,  when the Cent8 box
comes back up,  all the dummy adapters are missing.  I've been
searching all over trying to find some documentation on this to no
avail.  I'm hoping someone has some suggestions here to help out.

Thanks,
Frank

Anyone have any ideas?  It's rather annoying that I can't get these to
persist across reboots without using some kind of helper script.

On Fri, Oct 16, 2020 at 6:37 AM Frank Even
<lists+centos.org at elitists.org> wrote:
>
> Hello all, hoping someone can help me out here.
>
> I cannot get dummy interfaces on a new Cent8 build to persist across
reboots.
>
> On Cent7 - this is the process I use:
>
> Create Dummies:
> # cat /etc/modules-load.d/dummy.conf
> dummy
> # cat /etc/modprobe.d/dummyopts.conf
> options dummy numdummies=4
> # ip link add dummy0 type dummy
> ## - repeating a/ ascending dummyN adapters for as many needed
> # service network start
> # dracut -f
>
> Now  this  was  different than even how 6 handled it, forget how I
> finally dug that up (possible I even asked here).  I've applied this
> same configuration to a Cent8 box I'm trying to stand up and it all
> appears to work fine, but unlike the Cent7 boxes,  when the Cent8 box
> comes back up,  all the dummy adapters are missing.  I've been
> searching all over trying to find some documentation on this to no
> avail.  I'm hoping someone has some suggestions here to help out.
>
> Thanks,
> Frank

Have you tried to use NetworkManager ?
After all ,anything network related should be done by it.

[root at system ~]# nmcli connection add con-name dummy0 ifname dummy0 type
dummy ?
Connection 'dummy0' (9fdd74fa-c143-4991-9bac-0e542704ac89) successfully
added.

[root at system ~]# reboot
Shared connection to glustera closed.


[root at system ~]# uptime
03:23:44 up 0 min, ?1 user, ?load average: 1,57, 0,48, 0,17
[root at glustera ~]# nmcli connection show ?
NAME ???UUID ?????????????????????????????????TYPE ?????DEVICE ?
dummy0 ?9fdd74fa-c143-4991-9bac-0e542704ac89 ?dummy ????dummy0


[root at system ~]# ip a s dummy0
3: dummy0: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state
UNKNOWN group default qlen 1000
???link/ether ce:c9:83:97:10:ee brd ff:ff:ff:ff:ff:ff
???inet6 fe80::599:a978:9457:df10/64 scope link noprefixroute ?
??????valid_lft forever preferred_lft forever

P.S.: This is the first time I hear about dummy interfaces. What are those used
for ?

Best Regards,
Strahil Nikolov









? ???????, 27 ???????? 2020 ?., 02:42:06 ???????+2, Frank Even
<lists+centos.org at elitists.org> ??????:





Anyone have any ideas?? It's rather annoying that I can't get these to
persist across reboots without using some kind of helper script.

On Fri, Oct 16, 2020 at 6:37 AM Frank Even
<lists+centos.org at elitists.org> wrote:
>
> Hello all, hoping someone can help me out here.
>
> I cannot get dummy interfaces on a new Cent8 build to persist across
reboots.
>
> On Cent7 - this is the process I use:
>
> Create Dummies:
> # cat /etc/modules-load.d/dummy.conf
> dummy
> # cat /etc/modprobe.d/dummyopts.conf
> options dummy numdummies=4
> # ip link add dummy0 type dummy
> ## - repeating a/ ascending dummyN adapters for as many needed
> # service network start
> # dracut -f
>
> Now? this? was? different than even how 6 handled it, forget how I
> finally dug that up (possible I even asked here).? I've applied this
> same configuration to a Cent8 box I'm trying to stand up and it all
> appears to work fine, but unlike the Cent7 boxes,? when the Cent8 box
> comes back up,? all the dummy adapters are missing.? I've been
> searching all over trying to find some documentation on this to no
> avail.? I'm hoping someone has some suggestions here to help out.
>
> Thanks,
> Frank
_______________________________________________
CentOS mailing list
CentOS at centos.org
https://lists.centos.org/mailman/listinfo/centos

Have you tried with Network Manager , after all this is the thing that manages
all networks:


[root at system ~]# nmcli connection add con-name dummy0 ifname dummy0 type
dummy ?
Connection 'dummy0' (9fdd74fa-c143-4991-9bac-0e542704ac89) successfully
added.

 [root at system ~]#?reboot
Shared connection to glustera closed.

 [root at system ~]#?nmcli connection show ?
NAME ???UUID ?????????????????????????????????TYPE ?????DEVICE ?
dummy0 ?9fdd74fa-c143-4991-9bac-0e542704ac89 ?dummy ????dummy0


 [root at system ~]#?ip a s dummy0
3: dummy0: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state
UNKNOWN group default qlen 1000
???link/ether ce:c9:83:97:10:ee brd ff:ff:ff:ff:ff:ff
???inet6 fe80::599:a978:9457:df10/64 scope link noprefixroute ?
??????valid_lft forever preferred_lft forever


Best Regards,
Strahil Nikolov







? ???????, 27 ???????? 2020 ?., 02:42:06 ???????+2, Frank Even
<lists+centos.org at elitists.org> ??????:





Anyone have any ideas?? It's rather annoying that I can't get these to
persist across reboots without using some kind of helper script.

On Fri, Oct 16, 2020 at 6:37 AM Frank Even
<lists+centos.org at elitists.org> wrote:
>
> Hello all, hoping someone can help me out here.
>
> I cannot get dummy interfaces on a new Cent8 build to persist across
reboots.
>
> On Cent7 - this is the process I use:
>
> Create Dummies:
> # cat /etc/modules-load.d/dummy.conf
> dummy
> # cat /etc/modprobe.d/dummyopts.conf
> options dummy numdummies=4
> # ip link add dummy0 type dummy
> ## - repeating a/ ascending dummyN adapters for as many needed
> # service network start
> # dracut -f
>
> Now? this? was? different than even how 6 handled it, forget how I
> finally dug that up (possible I even asked here).? I've applied this
> same configuration to a Cent8 box I'm trying to stand up and it all
> appears to work fine, but unlike the Cent7 boxes,? when the Cent8 box
> comes back up,? all the dummy adapters are missing.? I've been
> searching all over trying to find some documentation on this to no
> avail.? I'm hoping someone has some suggestions here to help out.
>
> Thanks,
> Frank
_______________________________________________
CentOS mailing list
CentOS at centos.org
https://lists.centos.org/mailman/listinfo/centos