Questions tagged [virtio]
The virtio tag has no usage guidance.
51
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Is it possible to use the IO priority from a KVM guest on the host?
When I use KVM with libvirt and virtio block devices, does it propagate IO priority in some way? If the guest starts a process with ioidle priority, I want it to run only if the host is also in ioidle ...
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2
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724
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slow performance on ssd when using kvm to launch vm's
On my host hardware I have 1G's speed
on my vm I create using kvm it drops to around 20MB's
My host is running ubuntu 22.04 LTS
How can I optimise this?
I am using file based VM's. I created disk ...
- 351
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555
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libvirt/KVM 10Gb-capable network interface without virtio
Is there a way to set up a 10Gb-capable virtual ethernet port in a guest VM (RHEL) without using virtio ?
I have to put some kind of RHEL7 in a guest VM but the kernel used in there has UDP ...
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0
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252
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Does trim need to be enabled inside a VM on a zvol?
zfs and virtio both have trim support, which means, that trim operations can be forwarded by VMs using zvols to the physical underlaying disks. (Please excuse my usage of the word "physical zpool&...
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1
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549
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kvm / proxmox 5 - virtio_net slow network 5Mbit, sometimes 900Mbit in opposite or both direction
Environment:
several PROXMOX 5 (KVM) servers (kernel: 4.15.18-30-pve)
VMs running Debian 9, 10 and 11 (vitrio /qemu-guest-agent current version of the respective Debian version)
network cards ...
- 11
1
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1
answer
2k
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KVM with VirtioFS on host, Windows Server guest, VirtioFS access denied
I have some successful setups of Linux guests under KVM with VirtioFS, even able to boot from theese folders without any "classical" drive images or dedicated partitions.
Now, I have a need ...
- 234
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1
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4k
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Windows VM suddenly run very slow in KVM/QEMU
I have several times experience a Windows VM suddenly start to run extremely slow, seems mostly related to slow storage IO. Seen this in different versions, but in this particular case is Win10 LTSC ...
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1
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How to get Linux kernel to rescan virtio disks?
I have a virtio disk mounted to a KVM guest, backed by an LVM logical volume. I increased the size of the logical volume with lvresize on the KVM host machine.
Then I had to issue virsh pool-refresh ...
- 183
3
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1
answer
1k
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Updated VirtIO SCSI driver on my Windows 2012 R2, and now only boots into recovery. How to recover?
I have a Hetzner W2012 R2 Cloud VM, and I updated the VirtIO vioscsi driver on it. Now it only boots into recovery mode and I cannot access the C-drive even from command prompt.
Is there any way to ...
- 163
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392
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VirtIO ethernet adapter limited performance
I have a Windows 10 KVM VM on Ubuntu 20.04. The host has dual 10 GbE adapters configured as LACP bond and there's a bridge interface for the VM and it's on the same LAN as the host.
Windows has VirtIO ...
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1
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170
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Partition of mdadm raid0 array passed through to win10 20H2 via virto driver is suddenly lost. How can I figure out why?
I have checked the logs. System has been working for a month then suddenly they could not see the drive on network. It is a linux file server with a virtual windows on top of it ... Virtual windows ...
- 536
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1
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105
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number of read and write processes affect the io performance of different virtio-scsi luns
QEMU emulator version 2.9.0(qemu-kvm-ev-2.9.0-16.el7_4.11.1)
Linux 3.10.0-693.el7.x86_64
There are two luns attached via virtio-scsi (vcpu=1,virtio-scsi controller queue set to 1)
Firt:
dd /dev/sde ...
- 11
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0
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127
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Qemu Libvirt : unabled to pass all GPUs to vms
Im trying to pass all gpus to different systems , my setup:
asus x399 gaming 6 mainboard
amd 1950x
32G ram
1 TB intel ssd m.2
gtx970
gtx750
this resources should be passed into 3 systems:
vm1 a ...
- 103
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1
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286
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What is the role of QEMU in server virtualisation?
I am aware of that KVM provides hardware acceleration feature by utilises the virtualisation extension in CPU chips like Intel VT. So that VCPUs can be directly mapped to physical CPUs to achieve ...
- 103
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1
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(QEMU) Setup Windows 10 VM on a thinly-provisioned LVM device with discards (a.k.a. trim)
I'm trying to set up a Windows 10 VM using QEMU and I want to use a thinly-provisioned LVM volume and be able to "retrim" the drive in Windows. I created the device with:
-drive index=0,media=disk,...
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568
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KVM - Modify from IDE to VirtIO
I imported a CentOS 7 guest from XenServer to KVM.
After importing it into KVM the disk bus in use is the IDE.
I need to change the disk bus from IDE to VirtIO because VirtIO has better performance.
...
- 269
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0
answers
816
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Imbalanced IRQs on virtio devices
I noticed in the top on my linux server that one cpu had far more number of software interrupts than all other 7 cores. Digging further, I noticed that this core is pinned to a particular irq which ...
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751
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Is it possible to set an IO scheduler in KVM Guest with VirtIO?
Is it possible to set an IO scheduler in a KVM Guest with VirtIO?
With the following command i don't get any options to choose
cat /sys/block/vda/queue/schedule
none
Kerneloption are set:
root@...
- 131
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2k
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libvirt cannot boot windows-uefi guest with virtio storage
i have hyper-v gen2 win-guest and need to migrate on kvm with libvirt.
I convert one guest from vhdx to qcow2 with qemu-img, start it with qemu-system and hda-drive, install virtio drivers.
After that ...
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2
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qemu-kvm reclamation of memory from low-use guests
Is there a way to transparently reclaim, or prevent usage of, memory from a qemu-kvm guest?
Scenario A:
A guest uses 8GB of RAM during peak hours, it returns back to 4GB of usage at night, but the ...
- 800
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Unidentified network with VIRTIO NIC Drivers after system reboot
I have KVM with VIRTIO network interface. It runs under Windows Server 2012 R2 so I installed RedHat network virtio drivers. It runs properly but after system reboot internet connection is lost. ...
- 11
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1
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574
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windows guest OS over kvm hypervisor does not preserve disk status after attaching network interface
I have openstack based cloud environment. I have kvm/qemu based hypervisors. I created Windows guest OS vm on one of the hypervisors. And I attached volume(vhd) to vm. I changed disk status to online ...
- 175
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1
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845
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How to get a virtio disk to show up - kernel config
I'm trying to set up a Gentoo guest on a virtio drive. When I boot the VM using an ubuntu livecd, I do have a /dev/vda on which I installed the system using LVM.
I compiled a 4.9.16-gentoo kernel ...
- 387
1
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1
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249
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Why is posix.lstat taking such a long time? (duplicity backing up of 9p virtio filesystem)
I have a filesystem mounted with 9p virtio through KVM, and am backing it up using duplicity to a remote SSH server. I' m trying to speed up the backup process, which seems unreasonably slow to me.
...
- 51
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1
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2k
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Change Boot drive in SeaBios
I need to copy my KVM machine for further update.
BUT our provider don't provide opportunity to copy a whole machine, just a hard drive. (virtio drive vda/vdb etc)
So, I made a new clean machine, ...
- 129
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939
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RHEL 7.2 - cannot find attached vda disk during install via Mirantis Open Stack
In trying to install RHEL 7 from an ISO (instead of deploying from an existing KVM image) in Mirantis Open Stack, I run into Anaconda not being able to find the attached disk - and so installation ...
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0
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824
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Weird performace with VirtIO adapter in Linux Guest
I have been battling an extremely odd behavior with the VirtIO adapter for Linux KVM guests. First, my set up:
KVM host is a CentOS 6.8 box. Guests are running CentOS 7. The adapters were originally ...
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0
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639
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kvm virtualized Windows get low disk performances
Disclaimer
This is indeed a continuation of this thread. I've opened a new question as the target has slowly shifted, therefore I think was good to open a new post. I will merge back if required.
...
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639
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kvm virtio disk performance scales badly with iozone workload
I'm conducting a number of tests in order understand why some of our workloads generate a really poor "user experience" with db related activities.
We have a dl160g9 server with a B140i controller (4 ...
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1
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132
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How to make data up to date on a shareable disk connected to KVM guest?
I have 2 KVM guests running. One guest (let's call it the writing guest) writes to a virtio hdd (it's a lvm logical volume) periodically. Another guest (reading guest) reads from this disk (it's ...
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1k
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KVM/libvirt: Using virtio disk driver in Debian installer
I try to install Debian in a KVM-based VM using the virtio disk driver/bus and virt-install to run the installer.
However, it seems that the installer lacks the virtio driver. Once I switch to bus=...
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656
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Hardware raid, LVM and KVM cache policy
I have a question about right cache policy for KVM using LVM and hardware raid-controller.
So from the bottom:
1. We have LSI RAID controller 9260, 512Mb cache and BBU. Later we also will have ...
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3
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32k
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Get link speed of an virtio-net network adapter
I have an linux vm running on kvm with virtio-net, and I want to check the link speed. How can I do that?
What I tried so far:
# ethtool eth0
Settings for eth0:
Link detected: yes
It seems that ...
- 88
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0
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989
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How to switch in ws2012 from an IDE disk to a Virtio disk?
I am running Windows server 2012 in a virtual machine under Debian Jessie.
I tried to follow the Red Hat tutorial in order to switch on the Virtio drivers:
1) I downloaded from Debian the virtio ...
- 133
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3
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33k
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Install windows 2012 R2 over KVM-virtualizaton
I'm trying to install Windows Server 2012 R2 over linux KVM-virtualization.
The installation process stops and requires drivers to continue.
I'm trying with virtio drivers from fedora but doesn't ...
0
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1
answer
2k
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kvm/qemu host windows guest BSOD about driver_irql_not_less_or_equal for viostore.sys
I have a KVM/Qemu host running 4 Windows Server 2012 guests and after upgrading the host from Ubuntu 12.04 to 14.04 I get blue screens with a bug check string of "driver_irql_not_less_or_equal" that ...
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How to migrate from ide to virtio in RHEL 6.5 KVM guest with LVMs
I want to migrate a IDE-using, LVM-based KVM guest running RHEL 6.5. I found this steps in this page:
1) Run virsh edit . From there, edit the config file and
adjust all lines of
<target ...
- 133
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2
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Windows Server 2012 R2 doesn't find virtio drivers when installing on KVM
I'm trying to install Windows Server 2012 R2 on a Debian KVM host, but it does not seem to find the drivers.
The guest has two drives attached: an install disk and the latest Windows virtio drivers ...
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1
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613
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KVM Aggregate Throughput Limited at 1Gb - Virtio Queues Limiting Factor?
I have a KVM host with three NICs and can't get traffic between guests (in same subnet) above 1gbps aggregate. Is this by design and the only way to achieve >1gbps to use multiqueue support?
So far, ...
- 367
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1
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Installing VirtIO drivers on Win7
Context: I am attempting to convince a 64bit Win7 VirtualBox image to run under OpenStack, and Windows isn't my usual platform. Installing the Virtio drivers hasn't been going well. Thus far, what has ...
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3
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20k
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windows 7 as kvm guest installation with virtio drivers - detected virtio scsi disk shows wrong capacity
I am trying to install windows 7 64bit as a kvm guest.
I read here that I should install the virtio scsi driver during installation.
I use virt-install to start my installation from the command line
...
- 568
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1
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22k
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Poor network performance with KVM (virtio drivers) - Update: with vhost_net
I've set up several KVM based networks before, and never encountered this issue, can't for the life of me think what I'd have set up differently previously.
Setup
Basically, Ive got and entirely ...
- 463
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Ubuntu 14.04 KVM Host - Only network device pcnet working
I've installed a KVM host on Ubuntu 14.04. I've added a networking bridge as br0 and also added the p4p1 network adapter to it.
My problem is now that only the "pcnet" networking guest driver is ...
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2
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17k
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Can I have virtio-win package on CentOS?
In "Red Hat Enterprise Linux 6. Virtualization Host Configuration and Guest Installation Guide" in chapter 10.1 "Installing the KVM Windows para-virtualized drivers" it says:
The virtio-win package ...
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1
answer
2k
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Migrate CentOS VM using LVM on IDE to run with VirtIO
I'm trying to migrate existing IDE-using, LVM-based CentOS 5.2 VMs to use virtio. The symptom is a kernel panic upon boot when the system can't find any volume groups. Does anyone know how to make ...
5
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1
answer
3k
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Why is there a socket interface on the host and a character device interface on the guest for virtio-serial?
I am trying to establish a communication channel between the host and one of its guest virtual machine using kvm as a hypervisor. For this, I am using virtio-serial.
To create the virtual machine, I ...
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1
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KVM Win 7 Pro + RH virtio net driver
Host: Debian 7.2 x64.
Guest Win 7 Pro 32-bit. Virtio disk drivers work flawlessly, but there's a problem with virtio net (netkvm something) drivers. Virtio drivers come from virtio-win-0.1-74.iso.
...
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4
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9k
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How to efficiently share host's folder with KVM guests?
I am configuring the service which stores plenty of files uploaded by nginx in /srv/storage dir on host system. These files are processed by worker KVM guests which may create new files or assign ...
- 1,077
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1
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4k
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FreeBSD, VirtIO, and Virtualbox
I have no experience with VirtIO drivers, and am trying to figure out if it's possible to use them on this server.
The server is a FreeBSD 8.2-RELEASE host and ZFS file system, with a Virtual Box-...
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2
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Am I using virtio for my KVM guest?
In one of my KVM guest, when I typed the following command, I get the following
/sbin/lsmod | grep vi
virtio_balloon 3692 0
So does it mean I am using virtio?
Update:
When I type
cat "...
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