Cloudstack new kvm agent onboard error

[arpanbht]

Hey guys, recently in our private cloudstack setup we have added a new device - HPE DL385 Gen10+ v2. And we have it a kvm host just like we did before with our previous machines i.e. HP DL360 Gen10+.

We have added it as a agent in the management server but while we are trying to create on that host we are facing this error

2026-06-04 09:37:13,376 WARN  [kvm.resource.BridgeVifDriver] (AgentRequest-Handler-1:[]) (logid:4f6eb2d5) Execution of process [35869] for command [/usr/share/cloudstack-common/scripts/vm/network/vnet/modifyvlan.sh -v 2446 -p ens3f1np1 -b brens3f1np1-2446 -o add ] failed.
2026-06-04 09:37:13,376 WARN  [kvm.resource.BridgeVifDriver] (AgentRequest-Handler-1:[]) (logid:4f6eb2d5) Process [35869] for command [/usr/share/cloudstack-common/scripts/vm/network/vnet/modifyvlan.sh -v 2446 -p ens3f1np1 -b brens3f1np1-2446 -o add ] encountered the error: [Error: argument "brens3f1np1-2446" is wrong: "name" not a valid ifname/usr/share/cloudstack-common/scripts/vm/network/vnet/modifyvlan.sh: line 59: /proc/sys/net/ipv6/conf/brens3f1np1-2446/disable_ipv6: No such file or directoryCannot find device "brens3f1np1-2446"Failed to create br: brens3f1np1-2446].
2026-06-04 09:37:13,376 WARN  [resource.wrapper.LibvirtStartCommandWrapper] (AgentRequest-Handler-1:[]) (logid:4f6eb2d5) InternalErrorException com.cloud.exception.InternalErrorException: Failed to create vnet 2446: Error: argument "brens3f1np1-2446" is wrong: "name" not a valid ifname/usr/share/cloudstack-common/scripts/vm/network/vnet/modifyvlan.sh: line 59: /proc/sys/net/ipv6/conf/brens3f1np1-2446/disable_ipv6: No such file or directoryCannot find device "brens3f1np1-2446"Failed to create br: brens3f1np1-2446
        at com.cloud.hypervisor.kvm.resource.BridgeVifDriver.createVnet(BridgeVifDriver.java:338)
        at com.cloud.hypervisor.kvm.resource.BridgeVifDriver.createVnetBr(BridgeVifDriver.java:320)
        at com.cloud.hypervisor.kvm.resource.BridgeVifDriver.plug(BridgeVifDriver.java:239)
        at com.cloud.hypervisor.kvm.resource.LibvirtComputingResource.createVif(LibvirtComputingResource.java:3947)
        at com.cloud.hypervisor.kvm.resource.LibvirtComputingResource.createVifs(LibvirtComputingResource.java:3493)
        at com.cloud.hypervisor.kvm.resource.wrapper.LibvirtStartCommandWrapper.execute(LibvirtStartCommandWrapper.java:86)
        at com.cloud.hypervisor.kvm.resource.wrapper.LibvirtStartCommandWrapper.execute(LibvirtStartCommandWrapper.java:52)
        at com.cloud.hypervisor.kvm.resource.wrapper.LibvirtRequestWrapper.execute(LibvirtRequestWrapper.java:78)
        at com.cloud.hypervisor.kvm.resource.LibvirtComputingResource.executeRequest(LibvirtComputingResource.java:2336)
        at com.cloud.agent.Agent.processRequest(Agent.java:813)
        at com.cloud.agent.Agent$AgentRequestHandler.doTask(Agent.java:1295)
        at com.cloud.utils.nio.Task.call(Task.java:83)
        at com.cloud.utils.nio.Task.call(Task.java:29)
        at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
        at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
        at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
        at java.base/java.lang.Thread.run(Thread.java:829)

2026-06-04 09:37:13,377 INFO  [kvm.storage.LibvirtStorageAdaptor] (AgentRequest-Handler-1:[]) (logid:4f6eb2d5) Trying to fetch storage pool 81ecd9fd-9cdf-34cb-b99d-51d0e2cf3a0c from libvir

After analysing the error with claude it tell us that the bridge cloudstack creates i.e. brens3f1np1-2446 it says this vlan interface is 16 characters long but linux kernel caps interface names to maximum 15 characters , can it be a cause or is there any other thing we are missing out?

For your reference here is a bridge interface of our previous HP DL360 Gen10+

brens1f0-2446: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether ae:64:e5:8b:e0:c2 brd ff:ff:ff:ff:ff:ff

Please help 🙏

[weizhouapache]

@arpanbht
what cloude said is correct. please refer to #10190

you could rename the device or use alias name of the device

[arpanbht]

Thank you, let me try that and then I will come back

[arpanbht]

@weizhouapache Thank you man. Now its working fine, I can create vms on that host