KB

Product guides, component docs, and operations references for KB.

virtio-blk Discard capability limitation on a specific i440fx-compatible machine type

NIC names may change after upgrading the Mellanox driver in a Kylin ARM environment

AMD GPU passthrough compatibility limitation in a specific Kylin V10 kernel environment

Page may still show a healthy status after observability collection authentication fails

Update time does not refresh after observability log collection targets are changed

Observability log level filter may match keywords in the message text

Complete observability error information may be split into multiple log records

ZNS Network Service infrastructure capacity area may show no data or not applicable

Veeam API Proxy 1.0.4 installation fails because database objects remain after uninstalling 1.0.3

VNC console may show a black screen when a Windows VM instance uses a specific NVIDIA GPU as the display device

Default zone is not displayed or the embedded ZNS Network Center is inaccessible after installing ZNS from Application Market

Known limitation for cross-tier ZNS Network Service DNAT-LB on the same segment

Known limitation when a ZNS Network Service Tier-1 DNAT reuses the routing interface IP of its upstream Tier-0 gateway

LB_IP retention behavior for ZNS Network Service Layer 4 Load Balancing health monitors

Selected count is inaccurate when selecting ZNS Network Service Layer 4 Load Balancing pool members across pages

Pool member status may still be displayed as up after its segment is detached from Tier-1 in ZNS Network Service

ZNS Network Service Layer 4 Load Balancing may allow a segment network, gateway, or broadcast address to be used as a VIP

ZNS Network Service Layer 4 Load Balancing VIP does not consistently check all occupied or reserved IP addresses

A small number of connection timeouts or resets may occur under high-CPS short connections in ZNS Network Service OvsDpdk

Egress source address behavior when ZNS Network Service Reflexive NAT and higher-priority SNAT both match

Large-volume backup reports ioHung

Concurrent CBT and platform backup tasks for the same VM fail

Host enters emergency mode after storage is added through the UI and the host restarts

Live migration reports failure even though the VM has reached the destination host

SAN data storage VM enters file system emergency mode after OVA export and restart

Inconsistent bridge names for the same port group across hosts after a ZSphere upgrade

ZSphere CVE-2026-46333 / CVE-2026-43494 kernel vulnerability remediation

Patch for VM startup failure after custom XML configuration

Patch for GPU loss on VMs after DRS migration

Patch for abnormal list label display in ZStack Cloud

Patch for UI stalls when a sub-account deletes a scaling group

HCI Ultimate upgrade from 2.4.17 to 2.4.26

HCI Ultimate upgrade from 2.2.20 to 2.4.26

Adjust the RGW quota cache

Add a gateway network to the object service platform

Offline upgrade plan for a ZCE-X Ceph cluster

Scale in a ZCE-X Ceph storage cluster

ZCE-X Ceph Storage Node Scale-In and New Storage Pool Creation

Change the management network gateway address

Enable XDC kernel mode on new storage nodes

Upgrade the glib2 component on ZCE-X

Hot-swap a single OSD disk

Upgrade newly added ZCE-X storage nodes and enable XDC kernel mode

Rebalance an object storage data pool

Recover isolated OSDs in distributed storage

Replace a distributed storage cache disk

Replace a disk on a storage node

Replace a ZCE-X storage-node cache disk

Replace a ZCE-X storage-node data disk

Online upgrade of ZCE-X storage from 4.2.x to 5.2.x

Fix abnormal UI branding display for ZCE-X storage

Optimize deep-scrub scheduling

How do I safely adjust the ZCenter token expiration time when it does not meet business requirements?

Resolve ZCenter user login lockout

Upgrade ZStack Cloud from 4.4.x to 4.8.x

Upgrade ZStack Cloud from 4.8.x to 5.5.x

Upgrade ZStack Cloud from 5.3.x to 5.5.x

Upgrade ZStack Cloud 5.4.x to 5.4.7

Upgrade ZStack Cloud to 5.4.7

Upgrade ZStack Cloud to 5.4.x and Host Kernels to 4.18.0-553

Add a Heterogeneous Repository to Management Nodes

Clean Up Invalid CDP Backup Data

Upgrade Dual-Management ZStack Cloud to 5.4.x

Repair Dual-Management Database Desynchronization

Resynchronizing a dual-MN database and upgrading the zsha2 HA suite

Resyncing the ZStack Cloud management database on dual-MN HA after a power outage

Replacing the ZStack Cloud platform HTTPS certificate on dual-MN HA

Changing the time source (NTP) on a ZStack Cloud dual-MN HA deployment

Change the management network gateway on a host

Upgrade Host Kernels for ZStack Cloud 4.8.x

Upgrade Host Kernels to 553 for ZStack Cloud 5.5.x

Upgrade ZStack Cloud Host Kernels

Remediate CVE-2026-31431 on ZStack Cloud Hosts

Remediate CVE-2026-43284 on ZStack Cloud Hosts

One-Click Upgrade Script for ZStack Cloud

Remediate OpenSSH CVE-2024-6387 and Harden Port 8080 in ZStack Cloud

Upgrade OpenSSH for ZStack Cloud

Physical NIC disconnect and reconnect alarms caused by an unsupported SFP module

Port blocking and OpenSSH upgrade for ZStack Cloud

Update the RAID Controller Driver

Security hardening for ZStack Cloud

Upgrade ShareBlock sanlock in ZStack Cloud 4.4.x to address primary-storage connection failure and unreleased locks

Upgrade ShareBlock sanlock in ZStack Cloud 4.3.x to address stalled vgchange and unreleased locks

Correct a SharedBlock Volume Installation Path

Recover a Paused Thin-Provisioned VM

Remediate the vulnerability that permits Traceroute probes

VM creation fails because lvmlockd leaks VG shared locks after storage disconnects

VM live migration fails with rsync "connection unexpectedly closed" after the host root password is rotated

VM startup fails with "mediated device not found" after vGPU repartitioning

Harden VNC Console Passwords

Restrict access to VNC ports 5900 through 6050 in ZStack Cloud

Volume snapshot creation fails with "unable to find volume" due to a path mismatch

Enabling VPC network DHCP service and changing the DHCP service IP via zstack-cli

VPC vRouter creation times out because the VPC management network cannot reach the management node on TCP port 8080

Remediate Redis, etcd, and pprof vulnerabilities in ZStack Cloud

Block vulnerability scanner source addresses in ZStack Cloud

Harden Windows VM SMB Port 445 Exposure

Change the Time Zone for ZStack Cloud and a ZCE-X Cluster

Upgrade ZStack Cube HCI to 2.4.17 in a dual-management-node HA environment

Deleting an abnormal empty storage pool from a ZStone cluster

ZStone Cache Disk Data Flush

ZStone Storage Node Cache Disk Replacement

ZStone Hyperconverged Management Node Reinstallation and Recovery

ZStone Hyperconverged Node Memory Expansion

ZStone Primary Storage Trash Volume Cleanup and Space Reclamation

Rebuild PostgreSQL and Temporal on dual management nodes after a Temporal split-brain

Health check fails during Veeam API Proxy installation, but the service starts later

Veeam API Proxy times out connecting to a platform that uses a non-default HTTP port

Veeam Worker creation fails because no valid host is available

Veeam backup fails because data-agent is not healthy on port 16443

File-level restore is disabled for a Windows VM restore point in Veeam

Veeam Worker initialization stalls and the Worker does not shut down automatically

How do I troubleshoot a failure to add a cloud environment or test a cloud account connection?

How do I troubleshoot a ZCenter startup or API failure caused by a database connection issue?

How do I troubleshoot a ZCenter deployment or access failure caused by blocked ports?

Troubleshoot ZCenter Flyway database migration failures

How do I troubleshoot a Gateway 503 error that reports no available service instance?

How do I troubleshoot an inaccessible ZCenter page or API after enabling HTTPS?

How do I troubleshoot an empty ZCenter monitoring report or blank page?

How do I troubleshoot RabbitMQ when an order or operation remains in progress after its task finishes?

How do I identify and recover Redis when ZCenter login or resource synchronization fails?

Troubleshoot ZCenter resource synchronization failures

How do I troubleshoot a lock timeout that blocks synchronization for 1 cloud account or resource?

How do I troubleshoot repeated ZCenter service restarts after rebooting its VM?

How do I resolve requestTimeTooSkewed when ZCenter connects to ZSphere?

ZMigrate cannot retrieve platform data after a ZSphere platform connection is manually deleted

ZSphere migration fails API connectivity validation when adding the target environment

ZSphere migration protection process receiver or relay node option is locked

ZSphere migration cannot create the target host instance

ZSphere virtual machine cannot be cloned or the Clone button is unavailable

ZSphere cloning cannot find backup storage or commit a volume snapshot as an image

ZSphere OVF template import reports an expired upload session

ZSphere snapshot capacity is abnormal and no snapshot information appears in the UI

A ZSphere individual backup snapshot cannot be deleted from a UI snapshot group

Adding a ZSphere host fails because the management VLAN differs from the cluster default VLAN

ZSphere initialization or host addition fails because virtualization is not enabled

Adding a ZSphere HCI host reports failure to load the kvm_intel module

ZSphere installation cannot detect disks or the RAID controller driver is unsupported

ZSphere lacks a driver for the Huawei Hi1822 SP680 NIC

Updating ZSphere IPMI information fails to establish an RMCP+ session

ZSphere BMC or IPMI components cause abnormal host CPU utilization in a nested environment

ZSphere distributed switch cannot bind a bond NIC

Creating a ZSphere distributed port group with VLAN type None fails

ZSphere UI NIC status differs from the underlying system status

Adding ZSphere SAN data storage reports that an mpath device is in use

ZSphere cannot pass through LUNs to virtual machines with 3PAR iSCSI active-active storage

ZSphere upgrade fails with unknown variable wait_timeout

ZSphere management service fails to start and database user login fails after change_ip

ZSphere database startup failure when NTP is not configured on a single management node

Windows VM gateway missing after a ZSphere upgrade

VMTools installation fails on a ZSphere VM

Black screen in the console of a ZSphere Windows VM

Multiple ZSphere Windows VMs recover after manual startup following black screens or freezes

Hyper-V incompatibility when running a nested Workstation VM on ZSphere

Mitigate the RSA key exchange vulnerability on ZSphere HTTPS port 443

Validity-period limits for ZSphere self-signed certificates

Standard users cannot resize VM disks in ZSphere

Storage page exception after importing an HCI license following ZSphere takeover of ZStone

VM migration is not triggered after a NIC goes down under a ZSphere HA policy

Bulk HA VM migration in a ZSphere/ZStone environment

Test connection fails with "Cannot connect to LDAP/AD server" when adding an AD/LDAP server

Backup fails with block jobs not found or only found M

The host bond is removed after deleting a distributed switch

Full clone of an SBLK thick-provisioned disk fails because image storage has insufficient space

HA startup reports not enough capacity although the host has available CPU and memory

The management network becomes unreachable after adding an uplink to a host

Backup or snapshot request returns 408 Request Timeout

The management node fails to start and stops at LicenseManager during ZSphere installation

/etc/hosts permissions change to 0600 after changing the hostname of a Linux virtual machine

ZMigrate cannot retrieve ZSphere resources

UI remains in the Migrating state after changing the host, but no underlying task exists

Large-file backup to an NFS backup server fails with only found M block jobs

SharedBlock availableCapacity does not recover after Vinchin deletes a VM snapshot

A single-volume snapshot created by third-party software is not displayed or cannot be deleted normally in the ZSphere UI

Cross-cluster migration of a template-based VM fails with No host available

Veeam backup fails and an old CBT task remains in the Running state

Memory metrics are not displayed in advanced monitoring for a virtual machine

Installing VMTools reports that the virtual machine has no CD-ROM drive

Deleting a single-volume snapshot or snapshot group times out with "block job not finished"

VMTools is installed on a Windows virtual machine, but the platform shows it as not installed

Initial network configuration fails after hot-adding a VirtIO NIC to a Windows virtual machine

Windows Server 2025 VM blue-screens on restart after joining an AD domain with VMX enabled

A Windows virtual machine shows a Duplicate static IP and retains an APIPA address

VMTools status is abnormal on a Windows virtual machine, and VirtIO drivers show yellow warning icons

VMTools 1.5.9 is installed on a Windows virtual machine, but the platform still reports an outdated version

A100 GPU passthrough task timeout in ZStack Cloud

Troubleshooting ZStack Cloud API and SDK call issues

Periodic false positives from a ZStack Cloud arbitration alarm

Blank billing UI page in ZStack Cloud

How do I resolve a failure to create a VM instance on Ceph Enterprise primary storage?

Cross-subnet VNC remote login failure in ZStack Cloud

What can I do if pressing Ctrl+Alt+Del causes a host to disconnect?

Troubleshoot ZStack Cloud elastic BareMetal instance issues

Troubleshoot ZStack Cloud GPU and vGPU resource issues

Host memory usage is too high

Host restarts unexpectedly

chrony.conf configuration is reset after it is changed on a host

How do I adjust the cloud platform when changing a host switch port from Access to Trunk mode?

Running df -h on a host hangs

How do I troubleshoot a host hang by using netconsole?

VM instance cannot start after its host restarts

SSH connection to a host fails with “This key is not known by any other names”

Host network port status is down

Empty alarm content for a ZStack Cloud HTTP notification endpoint

Troubleshoot ZStack Cloud image template and image storage issues

Database installation fails while installing the management node service

Cloud platform monitoring data is not displayed

How do I migrate a VM instance from a KVM platform to ZStack Cloud?

Load balancer VIP is unreachable through ICMP

Management node and browser times differ because of clock drift

False alert for management-node data-directory usage in ZStack Cloud

Troubleshoot management-node database and cryptographic-plugin credential resource exceptions in ZStack Cloud

Management node CPU usage is high after zops tasks become stuck

Management node UI service fails because of incorrect /var/log permissions

SSH connection to a VM instance is slow although the network is normal

Adding a gateway node fails

ZStack Cloud platform access remains loading

Resource operations fail due to lvmlock result -28 on SharedBlock storage

UI cannot be opened after a single management node starts

Truncated SMS alarm content with ellipses in ZStack Cloud

Troubleshoot ZStack Cloud snapshot, cloning, and image creation issues

SSH sign-in to a VM instance fails

VM instance on local storage repeatedly restarts but cannot start

Volume on local storage cannot be accessed normally

Password cannot be changed online for an Ubuntu VM instance because qemu-guest-agent is outdated

ZStack Cloud UI alarm object does not match the actual resource

ZStack Cloud UI displays a blank page and the UI service is abnormal

Troubleshoot ZStack Cloud UI monitoring, alert, permission, and display issues

ZStack Cloud UI task progress is stuck and the VM list cannot load

Cloud platform cannot identify a USB device

How do I uninstall the Linux GuestTools?

Troubleshoot ZStack Cloud upgrade dependency and license issues

Hosts are disconnected after a cloud platform upgrade

Adding an image by URL fails

Userdata injection failure in ZStack Cloud

Windows VM startup failure after V2V migration in ZStack Cloud

How do I add multiple NICs to a VM instance?

VM instance is automatically paused

External service port connections are unstable after an EIP is attached to a VM instance

Troubleshoot a black VM instance console in ZStack Cloud

VM instance creation fails with “can't apply global Icelake-Server- x86_64-cpu.pconfig”

Creating an image from a VM instance is slow

DHCP prepare timeout during ZStack Cloud VM startup

Cloning a VM instance fails

VM HA does not trigger while a host is unresponsive but its storage heartbeat remains alive

Troubleshooting intermittent "Cannot assign requested address" errors when a VM accesses object storage

VM instance startup failure

Troubleshoot ZStack Cloud VM instance startup and operating system failures

Why do some VM instances take longer to shut down?

Unable to connect to a VM instance over SSH

VM instance network is abnormal after V2V migration

Expanded volume becomes unusable after a snapshot is created and reverted

Troubleshooting snapshot deletion when control-plane and data-plane chains are inconsistent

Troubleshoot incomplete VPC firewall rule delivery with VyOS in ZStack Cloud

VPC network is abnormal

Creating a VPC vRouter fails

Installing GuestTools on Windows displays “There is a problem with this Windows Installerpackage. A program run as partof the setup did not finish as expected Contact your supportpersonnel or package vendor”

Windows root-volume storage migration does not complete in ZStack Cloud

Windows VM console white screen and RDP login failure in ZStack Cloud

Windows VM instance cannot obtain an IP address

Windows VM instance cannot identify a newly added volume

ceph -s continues to report a clock skew warning after the cluster time is updated

Host addition fails because CentOS is replaced by Helix

Initial host addition fails and the system disk capacity is shown as 0

How to handle a large omap objects warning caused by too few object storage bucket shards

After a power-cycle test, all data disks are reported as unknown and the storage pool has stale PGs

Cannot download a request code from the ZStone page