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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"vTPM on KVM does not persist data (ACS 4.20.1.0, Ubuntu 24.04)","articleBody":"\u003e### problem\n\nafter a shutdown, the /var/lib/libvirt/swtpm/\u003cvmuuid\u003e which holds the tpm data is gone. When starting the vm again, the folder is re-created with empty tpm files.\n\nI am using a similar tpm definition  in manually configured kvm guests, if those vm are powered off the folder remains. \n\n### versions\n\n4.20.1.0\nUbuntu 24.04\n\n### The steps to reproduce the bug\n\n```\nroot@VM-647bf7bc-bdca-48fa-8329-8b7a103f9ab6:~# echo \"Hello, TPM!\" \u003e datafile\nroot@VM-647bf7bc-bdca-48fa-8329-8b7a103f9ab6:~# tpm2_nvwrite -C o -i datafile 0x1500016\nroot@VM-647bf7bc-bdca-48fa-8329-8b7a103f9ab6:~# tpm2_nvread -C o 0x1500016\nWARN: Reading full size of the NV index\nHello, TPM!\n```\n\nInstance power cycle, and tryi to read our value again from the tpm\n\n```\nroot@VM-647bf7bc-bdca-48fa-8329-8b7a103f9ab6:~# tpm2_nvread -C o 0x1500016\nWARN: Reading full size of the NV index\nWARNING:esys:src/tss2-esys/api/Esys_NV_ReadPublic.c:309:Esys_NV_ReadPublic_Finish() Received TPM Error\nERROR:esys:src/tss2-esys/esys_tr.c:243:Esys_TR_FromTPMPublic_Finish() Error NV_ReadPublic ErrorCode (0x0000018b)\nERROR:esys:src/tss2-esys/esys_tr.c:398:Esys_TR_FromTPMPublic() Error TR FromTPMPublic ErrorCode (0x0000018b)\nERROR: Esys_TR_FromTPMPublic(0x18B) - tpm:handle(1):the handle is not correct for the use\nERROR: Unable to run tpm2_nvread\nroot@VM-647bf7bc-bdca-48fa-8329-8b7a103f9ab6:\n```\n\n### What to do about it?\n\n_No response_","author":{"url":"https://github.com/jgotteswinter","@type":"Person","name":"jgotteswinter"},"datePublished":"2025-10-15T10:06:40.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":15},"url":"https://github.com/11842/cloudstack/issues/11842"}