I'm not sure what you mean be the prefix. You shouldn't have to put a
prefix before a VLAN id. Just Specify that you want to use VXLAN and
then link to the correct modifyvxlan.sh script (the EVPN-VXLAN script).
The default modifyvxlan.sh script assumes that you're using multicast
VXLAN (no underlay).
After you have chosen VXLAN for you guest networks, you'll get an option
to specify the range of VNI's you want. The evpn-vxlan script doesn't
care about the traffic label, so you can just put brcsmm1 or brvx to get
to the next config page, they won't be used anyway.
There should not be any vlan sub-interfaces for traditional bridge mode
(which you are using).
On 2/3/26 2:30 PM, Jan Vöhringer via users wrote:
Hi,
the vlan script will be executed because in the wizard i used only the number,
without vxlan:// prefix.
If no Prefix is given, VLAN will be used. I thought, if i choose type VXLAN,
the VNI will be used and not the VLAN-ID. (CloudStack 4.21.0.0 )
Because of that, I’m a step further now, but i don’t know how to use the Pubic
and Guest Traffic as VXLAN on a bridge (without an IP for the Hypervisor)
Should the Guest and Traffic also have a label and/or an VNI (or should i
create a dedicated bridge for Guest and Public)?
brvx is down until a VXLAN sub-interface is added…
[root@kvm01 ~]# brctl show
bridge name bridge id STP enabled interfaces
brcsmm1 8000.4ee1bcb57803 no vxlan1028
brdrbd1 8000.f6bdcd5a28d2 no vxlan1026
brvx 8000.000000000000 no
[root@kvm01 ~]# ip -br link show
lo UNKNOWN 00:00:00:00:00:00 <LOOPBACK,UP,LOWER_UP>
eno1 UP 00:0e:1e:96:a0:40
<BROADCAST,MULTICAST,UP,LOWER_UP>
eno2 UP 00:0e:1e:96:a0:42
<BROADCAST,MULTICAST,UP,LOWER_UP>
eno3 UP 00:0e:1e:96:a0:44
<BROADCAST,MULTICAST,UP,LOWER_UP>
eno4 UP 00:0e:1e:96:a0:46
<BROADCAST,MULTICAST,UP,LOWER_UP>
brdrbd1 UP f6:bd:cd:5a:28:d2
<BROADCAST,MULTICAST,UP,LOWER_UP>
vxlan1026 UNKNOWN f6:bd:cd:5a:28:d2
<BROADCAST,MULTICAST,UP,LOWER_UP>
brcsmm1 UP 4e:e1:bc:b5:78:03
<BROADCAST,MULTICAST,UP,LOWER_UP>
vxlan1028 UNKNOWN 4e:e1:bc:b5:78:03
<BROADCAST,MULTICAST,UP,LOWER_UP>
brvx DOWN 00:00:00:00:00:00
<NO-CARRIER,BROADCAST,MULTICAST,UP>
Jan
Von: Júlíus Þór Bess <[email protected]>
Datum: Dienstag, 3. Februar 2026 um 14:20
An: [email protected] <[email protected]>
Betreff: Re: AW: VXLAN-EVPN Bridge Name and Traffic Labels
Hi,
Please show the output of "brctl show" and "ip -br link show"
I suspect the GUEST network is inheriting brcsmm1 from Management since
GUEST is not assigned a label.
On 2/3/26 6:31 AM, Jan Vöhringer via users wrote:
Hi Júlíus,
thank you for your message.
i’ve created again a new zone (new DB from scratch) and do following traffic
tags:
Physical Network 1, Isolation Method: VXLAN
*
GUEST (without Label)
*
MANAGEMENT (brcsmm1)
*
PUBLIC (without Label)
*
STORAGE (brdrbd1)
log show: Error: argument "brvxlan1028-1096" is wrong: "name" not a valid
ifname Failed to create br: brvxlan1028-1096
Failed to create vnet 1096: Error: argument "brvxlan1028-1096" is wrong: "name" not a
valid ifname/usr/share/cloudstack-common/scripts/vm/network/vnet/modifyvlan.sh: line 59:
/proc/sys/net/ipv6/conf/brvxlan1028-1096/disable_ipv6: No such file or directoryCannot find device
"brvxlan1028-1096"Failed to create br: brvxlan1028-1096
brvxlan1028-1096 - don’t know why this is used or created, brvxlan1028 is
brcsmm1 with subinterface vxlan1028
1096 is my public guest Network, but i didn’t used it in the wizard.
and i can’t explain why still modifyvlan instead of modifyvxlan is used.
Maybe if NO Traffic Label is set, it uses modifyvlan?
Best Regards,
Jan
Von: Júlíus Þór Bess <[email protected]>
Datum: Montag, 2. Februar 2026 um 18:10
An: [email protected] <[email protected]>
Betreff: Re: VXLAN-EVPN Bridge Name and Traffic Labels
Hi Jan,
Max ifname length is 15 characters, so yes. The ifname of
brvxlan1028-1096 is too long.
Did you replace the modify-vxlan.sh with the EVPN-VXLAN version?
Otherwise you're using the multicast version.
I also notice that the modifyvlan.sh (notice vlan, not vxlan) is
executing and trying to create a VLAN on a traditional bridge... That's
probably not what you want. What should happen is that modifyvxlan.sh
should have created another bridge named brvx1096 which should have a
bridge slave of vxlan1096. Names might not be entirely correct but you
probably get what I mean.
On 2/2/26 4:56 PM, Jan V�hringer via users wrote:
Hi Cloudstack Community,
i have trouble with the Zone/Welcome Wizard in Cloudstack - the System
VMs are in a deployment/reboot loop.
Maybe because of the wrong or too long Bridge Name for VXLAN with EVPN.
*
Setup modify sh for VXLAN with EVPN
*
The Hosts have two physical NICs:
o
eno1 = Transfer LAN-1 OSPF 172.16.11.2/30
o
eno2 = Transfer LAN-2 OSPF 172.16.12.2/30
o
lo = Loopback for BGP with EVPN 10.1.0.1/32
o
brdrbd1 = Bridge for DRBD / Linstor Traffic 10.10.26.101 /24
+
vxlan1026 as Subinterface, added by NMCLI
o
brcsmm1 = Bridge for Cloudstack Management Traffic
10.10.28.101 /24
+
vxlan1028 as Subinterface, added by NMCLI
i’m looking for „normal“ VXLAN Bridges like brvxlan2001 for example
customer1...
After the Wizard completes, the Systems VMs are permanently
rebooted/deployed. And the Wizard create following Interfaces: cloud0
and vxlan1028.1096@vxlan1028
Log Show (1096 should be the public VXLAN):
"“result”:“false”,“details”:“Failed to create vnet 1096: Error:
argument \"brvxlan1028-1096\" is wrong: \"name\" not a valid ifname...
Cannot find device \"brvxlan1028-1096\" Failed to create br:
brvxlan1028-1096”
Failed to create vnet 1096: Error: argument "brvxlan1028-1096" is
wrong: "name" not a valid
ifname/usr/share/cloudstack-common/scripts/vm/network/vnet/modifyvlan.sh:
line 59: /proc/sys/net/
ipv6/conf/brvxlan1028-1096/disable_ipv6: No such file or
directoryCannot find device "brvxlan1028-1096"Failed to create br:
brvxlan1028-1096
i’ve following setups without success:
SCR-20260129-kvah.png
and
image.png
have someone a idea how to create the Interfaces and Traffic Types?
Best Regards,
Jan
