Peran bawaan ini berisi
izin yang diperlukan untuk menyelamatkan VM. Untuk melihat izin yang benar-benar diperlukan, luaskan bagian Izin yang diperlukan:
Izin yang diperlukan
Izin berikut diperlukan untuk menyelamatkan VM:
compute.instances.create
di project
compute.disks.create
di project
compute.instances.get
di project
compute.disks.createSnapshot
pada disk
compute.instances.attachDisk
pada VM baru
compute.disks.use
pada disk
compute.instances.start
pada VM baru dan yang tidak dapat diakses
compute.instances.stop
pada VM baru dan yang tidak dapat diakses
Untuk setiap snapshot boot disk VM yang tidak dapat diakses yang Anda buat sebelumnya, buat disk baru dari snapshot dan pasang ke VM penyelamat dengan melakukan hal berikut:
Di konsol Google Cloud , buka halaman VM instances.
Identifikasi nama setiap disk yang sebelumnya Anda pasang ke
VM dengan menjalankan perintah berikut:
lsblk -d -o NAME,SERIAL
Outputnya mirip dengan hal berikut ini:
NAME SERIAL
sda rescue-vm
sdb my-recovery-disk
Dalam contoh ini, rescue-vm adalah boot disk VM penyelamat dan
my-recovery-disk adalah boot disk dari snapshot VM yang tidak dapat diakses. Catat NAME VM yang tidak dapat diakses untuk digunakan pada langkah berikutnya.
Untuk setiap disk yang sebelumnya Anda pasang ke VM, lakukan hal berikut:
Identifikasi sistem file setiap partisi dengan menjalankan perintah
berikut:
fdisk -l /dev/NAME -o Device,Size,Type
Ganti NAME dengan nama disk boot VM yang tidak dapat diakses dari langkah sebelumnya. Dalam contoh ini, namanya adalah
sdb.
Outputnya mirip dengan hal berikut ini:
Disk /dev/sdb: 10 GiB, 10737418240 bytes, 20971520 sectors
Disk model: PersistentDisk
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Disk identifier: B31430F1-F041-4555-96B9-B2F43DC057AD
Device Size Type
/dev/sdb1 2M BIOS boot
/dev/sdb2 20M EFI System
/dev/sdb3 10G Linux filesystem
Kolom Type mencantumkan sistem file setiap partisi. Jika jenis sistem file tidak ada untuk partisi apa pun, jalankan perintah berikut:
file -sL /dev/PARTITION_NAME
Ganti NAME dengan nama partisi.
Outputnya berbeda-beda, bergantung pada jenis sistem file:
Tidak ada sistem file: Jika output hanya menampilkan data, partisi tidak berisi sistem file. Contoh output:
/dev/sdb1: data
Sistem file EFI: Jika output menjelaskan sektor booting DOS/MBR,
partisi memiliki sistem file EFI. Contoh output:
Ganti PARTITION_NAME dengan nama sistem file Linux
yang Anda catat sebelumnya.
Jika Anda ingin mengubah direktori root sistem file menggunakan perintah
chroot, Anda juga harus memasang sistem file dan perangkat virtual
dengan menjalankan perintah berikut:
sudo mount -t proc /proc /rescue/proc
sudo mount -t sysfs /sys /rescue/sys
sudo mount -o bind /dev /rescue/dev
sudo mount -o bind /dev/pts /rescue/dev/pts
sudo mount -o bind /run /rescue/run
Sistem file disk boot yang tidak dapat diakses kini terpasang di /rescue.
Anda dapat menjelajahi sistem file, mengubah file konfigurasi, memperbaiki masalah, atau mengambil data.
Kembalikan perubahan dan lakukan lagi booting VM yang tidak dapat diakses
Setelah masalah diperbaiki atau data diambil, Anda harus mengembalikan VM yang sebenarnya. Lakukan langkah-langkah berikut untuk memulihkan VM asli:
Lepaskan disk tambahan yang terpasang di /rescue di VM sementara:
cd ~
sudo umount /rescue
Di konsol Google Cloud , buka halaman VM instances.
[[["Mudah dipahami","easyToUnderstand","thumb-up"],["Memecahkan masalah saya","solvedMyProblem","thumb-up"],["Lainnya","otherUp","thumb-up"]],[["Sulit dipahami","hardToUnderstand","thumb-down"],["Informasi atau kode contoh salah","incorrectInformationOrSampleCode","thumb-down"],["Informasi/contoh yang saya butuhkan tidak ada","missingTheInformationSamplesINeed","thumb-down"],["Masalah terjemahan","translationIssue","thumb-down"],["Lainnya","otherDown","thumb-down"]],["Terakhir diperbarui pada 2025-09-09 UTC."],[[["\u003cp\u003eThis document outlines the steps to rescue an inaccessible Linux VM by creating a temporary VM and attaching a snapshot of the inaccessible VM's boot disk.\u003c/p\u003e\n"],["\u003cp\u003eSpecific IAM roles, such as Compute Instance Admin (v1) and Service Account User, are required to perform VM rescue operations, which are needed to access the necessary permissions for creating, attaching, and managing disks and instances.\u003c/p\u003e\n"],["\u003cp\u003eTo rescue a VM, you must create a snapshot of the inaccessible VM's boot disk, create a temporary VM, attach the snapshot as a disk to the temporary VM, and then mount and access the file system for data retrieval or issue resolution.\u003c/p\u003e\n"],["\u003cp\u003eAfter resolving issues or retrieving data, the process involves unmounting the recovery disk from the temporary VM, detaching the original boot disk from the inaccessible VM, attaching the fixed disk, and restarting the original VM.\u003c/p\u003e\n"],["\u003cp\u003eConnecting to the temporary and the fixed VM is done via ssh, which can be done by following the documentation provided.\u003c/p\u003e\n"]]],[],null,["# Rescue an inaccessible VM\n\nLinux\n\n*** ** * ** ***\n\nIf your Linux VM is inaccessible due to any reason, you can try rescue the\nVM using the following steps.\n\nRequired roles\n--------------\n\n\nTo get the permissions that\nyou need to rescue a VM,\n\nask your administrator to grant you the\nfollowing IAM roles on the project:\n\n- [Compute Instance Admin (v1)](/iam/docs/roles-permissions/compute#compute.instanceAdmin.v1) (`roles/compute.instanceAdmin.v1`)\n- VMs that use a service account: [Service account user](/iam/docs/roles-permissions/iam#iam.serviceAccountUser) (`roles/iam.serviceAccountUser`)\n\n\nFor more information about granting roles, see [Manage access to projects, folders, and organizations](/iam/docs/granting-changing-revoking-access).\n\n\nThese predefined roles contain\n\nthe permissions required to rescue a VM. To see the exact permissions that are\nrequired, expand the **Required permissions** section:\n\n\n#### Required permissions\n\nThe following permissions are required to rescue a VM:\n\n- ` compute.instances.create` on project\n- ` compute.disks.create` on project\n- ` compute.instances.get` on project\n- ` compute.disks.createSnapshot` on disks\n- ` compute.instances.attachDisk` on new VM\n- ` compute.disks.use` on disk\n- ` compute.instances.start` on new and inaccessible VM\n- ` compute.instances.stop` on new and inaccessible VM\n\n\nYou might also be able to get\nthese permissions\nwith [custom roles](/iam/docs/creating-custom-roles) or\nother [predefined roles](/iam/docs/roles-overview#predefined).\n\nRescue a VM\n-----------\n\nIf you can't connect to your VM, or your boot disk is full, you must\ncreate a temporary VM to rescue the inaccessible VM.\n\n1. (Optional) Stop the inaccessible VM.\n2. [Create a snapshot](/compute/docs/disks/create-snapshots#creating_snapshots) from the boot disk of the inaccessible VM. If the root file system is split across multiple disks, you must snapshot each disk.\n3. [Create a temporary VM using a public image closest to inaccessible VM's OS](/compute/docs/images#list_of_public_images_available_on). In some cases a trusted image policy might restrict you from creating boot disks from public images. In such cases you must ask an administrator to temporarily lift this restriction before you can create a rescue VM. See [Set image access constraints](/compute/docs/images/restricting-image-access#trusted_images) for more information.\n4. For each of the snapshots of the inaccessible VM's boot disks you\n previously created, create a new disk from the snapshot and attach it to\n the rescue VM by doing the following:\n\n 1. In the Google Cloud console, go to the **VM instances** page.\n\n [Go to VM instances](https://console.cloud.google.com/compute/instances)\n 2. Click the name of the temporary VM that you created.\n\n 3. Click edit **Edit**.\n\n 4. Under **Additional disks** , click\n add**Add new disk**, and then do\n the following:\n\n 1. Add the disk name, like \u003cvar translate=\"no\"\u003emy-recovery-disk\u003c/var\u003e\n 2. For **Source type** , select the **Snapshot** tab.\n 3. In the **Source snapshot** drop-down menu, select the snapshot of the source VM that you created earlier in these steps.\n 4. Click **Done**.\n 5. Click **Save**.\n\n5. [Connect to the temporary VM](/compute/docs/instances/connecting-to-instance#connecting_to_vms)\n using SSH.\n\n6. Identify the name of each of the disks that you previously attached to\n the VM by running the following command:\n\n \u003cbr /\u003e\n\n ```\n lsblk -d -o NAME,SERIAL\n ```\n\n \u003cbr /\u003e\n\n The output is similar to the following:\n\n \u003cbr /\u003e\n\n ```\n NAME SERIAL\n sda rescue-vm\n sdb my-recovery-disk\n \n ```\n\n \u003cbr /\u003e\n\n In this example, `rescue-vm` is the boot disk of the rescue VM and\n `my-recovery-disk` is the boot disk from the snapshot of the inaccessible\n VM. Note the `NAME` of the inaccessible VM for use in the next\n step.\n7. For each of the disks that you previously attached to the VM, do the\n following:\n\n 1. Identify the file system of each partition by running the following\n command:\n\n ```\n fdisk -l /dev/NAME -o Device,Size,Type\n ```\n\n Replace \u003cvar translate=\"no\"\u003eNAME\u003c/var\u003e with the name of the inaccessible\n VM's boot disk from the previous step. In this example, the name would\n be `sdb`.\n\n The output is similar to the following: \n\n ```\n Disk /dev/sdb: 10 GiB, 10737418240 bytes, 20971520 sectors\n Disk model: PersistentDisk\n Units: sectors of 1 * 512 = 512 bytes\n Sector size (logical/physical): 512 bytes / 4096 bytes\n I/O size (minimum/optimal): 4096 bytes / 4096 bytes\n Disklabel type: gpt\n Disk identifier: B31430F1-F041-4555-96B9-B2F43DC057AD\n\n Device Size Type\n /dev/sdb1 2M BIOS boot\n /dev/sdb2 20M EFI System\n /dev/sdb3 10G Linux filesystem\n ```\n\n The `Type` column lists the file system of each partition. If the file\n system type is missing for any partitions, run the following command: \n\n ```\n file -sL /dev/PARTITION_NAME\n ```\n\n Replace \u003cvar translate=\"no\"\u003eNAME\u003c/var\u003e with the name of the partition.\n\n The output differs depending on the file system type:\n - **No file system** : If the output only displays `data`, the partition\n doesn't contain a file system. Example output:\n\n ```\n /dev/sdb1: data\n ```\n - **EFI file system**: If the output describes a DOS/MBR boot sector,\n the partition has an EFI file system. Example output:\n\n ```\n dev/sdb2: DOS/MBR boot sector, code offset 0x3c+2, OEM-ID \"mkfs.fat\", sectors/cluster 4, reserved sectors\n 4, root entries 512, sectors 40960 (volumes \u003c=32 MB), Media descriptor 0xf8, sectors/FAT 40, sectors/\n track 32, heads 64, serial number 0xf2af2664, label: \"EFI \", FAT (16 bit)\n ```\n - **Linux file system**: If the output describes file system data, the\n partition is a Linux file system. Example output:\n\n ```\n /dev/sdb3: SGI XFS filesystem data (blksz 4096, inosz 512, v2 dirs)\n ```\n\n Note the partition name of the Linux file system.\n 2. Create a mount point at `/rescue`:\n\n ```\n sudo mkdir /rescue\n ```\n 3. Mount the Linux file system partition to `/rescue`:\n\n ```\n sudo mount PARTITION_NAME /rescue\n ```\n\n Replace \u003cvar translate=\"no\"\u003ePARTITION_NAME\u003c/var\u003e with the name of the Linux file system\n you previously noted.\n 4. If you want to modify the root directory of the file system using the\n `chroot` command, you must additionally mount the virtual file system\n and devices by running the following commands:\n\n ```\n sudo mount -t proc /proc /rescue/proc\n sudo mount -t sysfs /sys /rescue/sys\n sudo mount -o bind /dev /rescue/dev\n sudo mount -o bind /dev/pts /rescue/dev/pts\n sudo mount -o bind /run /rescue/run\n ```\n\n The inaccessible boot disk's file system is now mounted at `/rescue`.\n You can navigate the file system, change config files, fix issues or\n retrieve the data.\n\nRevert the changes and boot the inaccessible VM back\n----------------------------------------------------\n\nAfter the issue is fixed or data is retrieved, you need to bring back the actual\nVM. Use the following steps to restore the original VM:\n\n1. Unmount the additional disk which is mounted at `/rescue` in the\n temporary VM:\n\n \u003cbr /\u003e\n\n ```\n cd ~\n sudo umount /rescue\n ```\n\n \u003cbr /\u003e\n\n2. In the Google Cloud console, go to the **VM instances** page.\n\n [Go to VM instances](https://console.cloud.google.com/compute/instances)\n 1. Select the temporary VM that you created.\n\n 2. Click edit**Edit**.\n\n 3. Under **Additional disks** , click close\n for the disk created in earlier steps to detach the additional\n disk from the temporary VM.\n\n 4. Click **Save**.\n\n3. Go to the **VM instances** page in the Google Cloud console.\n\n [Go to VM instances](https://console.cloud.google.com/compute/instances)\n 1. If the inaccessible VM is still running, [stop the VM](/compute/docs/instances/stop-start-instance#stop-vm).\n\n 2. Click the name of the VM you just stopped, and then click\n edit**Edit**.\n\n 3. Under **Boot disk** , click close\n **Detach book disk** to detach the exiting boot disk from\n the inaccessible VM.\n\n 4. Next, click edit **CONFIGURE BOOT\n DISK** to attach the disk you created and fixed previously in\n [Rescue a VM](#rescue) on this page.\n\n 1. In the **Boot Disk** section, click the **Existing disks** tab.\n 2. In the drop-down list, select the disk that you created in the previous section, for example `my-recovery-disk`.\n 3. Click **Select** and then click **Save**.\n 5. [Start the VM](/compute/docs/instances/stop-start-instance#starting_a_stopped_instance).\n\n4. You should now be able to [connect to the VM](/compute/docs/instances/connecting-to-instance#connecting_to_vms)\n using SSH."]]
