@ddstreet Thanks for your advice,
FYI, This symptom is only happening when backend storage is LVM, it is ok when we just use local storage And I've checked decoded string before but it was the same (error). LVM has error, local is ok But I'm trying to test you mentioned Thanks -- You received this bug notification because you are a member of STS Sponsors, which is subscribed to the bug report. https://bugs.launchpad.net/bugs/1921658 Title: Can't compose kvm host with lvm storage on maas 2.8.4 Status in MAAS: Triaged Status in readline package in Ubuntu: Fix Released Status in readline source package in Bionic: Incomplete Bug description: [Impact] I can't compose kvm host on maas 2.8.4 ( bionic) I upgraded twisted and related component with pip but the symptom is the same. MaaS 2.9.x in Focal works fine. in 2.8.x, pexpect virsh vol-path should return [2] but returns [3] [2] /dev/maas_data_vg/8d4e8b04-4031-4a1b-b5f2-a8306192db11 [3] 2021-03-17 20:43:34 stderr: [error] Message: 'this is the result...\n' 2021-03-17 20:43:34 stderr: [error] Arguments: ([' ', '<3ef-46ca-87c8-19171950592f --pool maas_guest_lvm_vg', "error: command 'attach-disk' doesn't support option --pool"],) sometimes it fails in def get_volume_path(self, pool, volume): """Return the path to the file from `pool` and `volume`.""" output = self.run(["vol-path", volume, "--pool", pool]) return output.strip() sometimes failes in def get_machine_xml(self, machine): # Check if we have a cached version of the XML. # This is a short-lived object, so we don't need to worry about # expiring objects in the cache. if machine in self.xml: return self.xml[machine] # Grab the XML from virsh if we don't have it already. output = self.run(["dumpxml", machine]).strip() if output.startswith("error:"): maaslog.error("%s: Failed to get XML for machine", machine) return None # Cache the XML, since we'll need it later to reconfigure the VM. self.xml[machine] = output return output I assume that run function has issue. Command line virsh vol-path and simple pepect python code works fine. Any advice for this issue? Thanks. [Test Plan] 0) deploy Bionic and MAAS 2.8 1) Create file to be used as loopback device sudo dd if=/dev/zero of=lvm bs=16000 count=1M 2) sudo losetup /dev/loop39 lvm 3) sudo pvcreate /dev/loop39 4) sudo vgcreate maas_data_vg /dev/loop39 5) Save below xml: <pool type='logical'> <name>maas_guest_lvm_vg</name> <source> <name>maas_data_vg</name> <format type='lvm2'/> </source> <target> <path>/dev/maas_data_vg</path> </target> </pool> 6) virsh pool-create maas_guest_lvm_vg.xml 7) Add KVM host in MaaS 8) Attempt to compose a POD using storage pool maas_guest_lvm_vg 9) GUI will fail with: Pod unable to compose machine: Unable to compose machine because: Failed talking to pod: Start tag expected, '<' not found, line 1, column 1 (<string>, line 1) [Where problems could occer] This patch is small peice of huge commit. I tested by compiling test pkg with this patch. but actually it is kind of underlying library ( libreadline ), so It could affect to any application using libreadline. e.g running command inside application by code can be affected. [Other Info] To manage notifications about this bug go to: https://bugs.launchpad.net/maas/+bug/1921658/+subscriptions -- Mailing list: https://launchpad.net/~sts-sponsors Post to : [email protected] Unsubscribe : https://launchpad.net/~sts-sponsors More help : https://help.launchpad.net/ListHelp

