Configure system parameters

Perform this task to configure the global parameters of CVM.

System parameters include the following:

• Basic System Parameters—Configure basic parameters of CVM.

• Customization Parameters—Configure CVM interface customization parameters.

• Customized Menu Parameters—Configure the customized menu parameters used to access other systems.

• VNC Proxy Server Parameters—Configure VNC proxy server parameters.

Virtual Network Computing (VNC) enables you to remotely control another computer. It transmits the remote computer screen to the local over the network. VNC consists of VNC clients and VNC servers. The VM consoles in CVM are VNC clients and VMs on the hosts are VNC servers. Operators might access the VMs within the data center from an external network. As a best practice to ensure data security, specify a VNC proxy server for the VMs. The VNC proxy server is the only node that the data center exposes to external networks. The external network can communicate with VMs within the data center only through the VNC proxy server.

• HA Parameters—Configure the host heartbeat interval and the storage heartbeat interval. The host heartbeat and storage heartbeat enables CVM to manage hosts, monitor HA resources, detect failed hosts and VMs in the cluster, and migrate VMs to available hosts.

• Image Clean Up—Set the resource usage thresholds for cached images saved in /vms/nova, for example, cached images for interoperation with CloudOS and native OpenStack. The system will clean up cached images that exceed the usage thresholds automatically.

• CPU and Memory Parameters—Set the maximum VM CPU and memory allocation ratios for each host. The system no longer creates VMs on a host if one of the ratio is reached.

• Upgrade Parameters—Set the graceful VM shutdown period and graceful host recovery period during the host upgrade process.

Procedure

1. On the top navigation bar, click System.

2. From the left navigation pane, select Parameters.

3. Click the System Parameters tab.

4. Configure basic system parameters, customization parameters, customized menu parameters, VNC proxy server parameters, HA parameters, image cleanup parameters, and CPU and memory parameters, as described in "Parameters."

5. Click Save.

Parameters

Basic System Parameters

• Idle Timeout: Specify the idle timeout for the operators. An operator automatically logs out of the system when the idle timeout expires.

• Lockout Period: Specify the time period during which the IP address that an operator uses to access the system is forbidden from logging in to the system. The timer starts for an operator's IP address after the operator fails to log in to the system consecutively for the specified times.

• Max Login Attempts: Specify the maximum number of allowable consecutive login failures. If an operator fails to log in to the system for the specified times, the operator's IP address cannot log in to the system within the specified time period.

• Max Online Operators: Specify the maximum number of online operators. 0 indicates that the number of online operators is not limited.

• Log Level: Select a log level. Options include Error, Warning, and Tip.

• Monitor Refresh Interval: Select the refresh interval for the monitoring information about hosts and VMs. Options include 30 sec, 1 min, 5 min, and 10 min.

• Alarm Lifetime: Specify the lifetime period of alarms. If the monitor data lifetime is longer than 7 days, make sure the root partition on the single management host or the mysql-share partition on the stateful failover system has enough space. If you fail to do so, system faults might occur.

• Recycled VM Lifetime: Specify the lifetime period of VMs in the recycle bin. The system automatically deletes a VM in the recycle bin after the lifetime period of the VM expires. The value of 0 indicates that VMs in the recycle bin will not be automatically deleted.

• Monitor Data Lifetime: Specify the lifetime period of the performance monitoring data.

• Monitoring Data Polling Interval: Select the interval at which the system collects the CPU, memory, disk, and network performance data of hosts and VMs. After you select an interval, the performance monitoring pages display performance monitoring data collected at this interval.

• Temporary File Directory: Enter a temporary directory for uploaded and downloaded files.

• Migration Pause Period: Set the VM pause period for migrating the remaining dirty pages before online migration is completed. As a best practice, do not set this parameter.

• Operation Log Lifetime: Specify the time period within which operation logs cannot be deleted.

• Encoding Mode: Select the encoding mode that the hosts use to report alarms to the alarm server. Options include BASE64, GBK, and UTF-8.

• Intel RDT Noisy Neighbor Quieting: Select whether to enable Intel RDT noisy neighbor quieting. After you enable this feature on the system parameter configuration page, you can enable this feature for a VM on the VM editing page. To enable Intel RDT noisy neighbor quieting for a VM, make sure the physical CPUs on the host where the VM resides support this feature.

• Max External Snapshots: Specify the maximum number of external snapshots that can be stored for a VM.

• Max Client Connection: Specify the maximum number of connections that an IP address can establish to CVM.

• Start VM MAC Address: Specify a MAC address in the range of 0c:da:41:1d:03:30 to 0c:da:41:1d:ef:a8. The start VM MAC address is the start address of the MAC address pool used for VM MAC address allocation. A VM does not release its allocated MAC address when it is converted to a VM template.

• End VM MAC Address: Specify a MAC address in the range of 0c:da:41:1d:16:b8 to 0c:da:41:1e:03:30. The end VM MAC address is the end address of the MAC address pool used for VM MAC address allocation. A VM does not release its allocated MAC address when it is converted to a VM template.

• Storage Pool Level-2 Directory: Enable the system to create level-2 directories for VMs in storage pools.

• With this feature enabled, the system automatically creates a level-2 directory named VM name_dir in the root directory of a storage pool to store a VM image file when you perform an operation that creates the VM image file, such as deploying a VM.

• With this feature disabled, the system does not create level-2 directories in storage pools, and existing level-2 directories are still available for use.

• Shared Storage Fault Action: Select the action to take when the shared storage of a host fails. Options include Restart Host and Do Not Restart Host.

• VM IPv6 Address Management: Select whether to enable IPv6 configuration for VMs. If you select Yes, you can configure IPv6 addresses for VMs when you add, Edit, or clone VMs, or deploy VMs through templates. When you view information about a VM, its IPv6 address is displayed.

• DRX VM Startup: Set the state of DRX VM startup. With this function enabled, the system checks whether a host meets the VM startup requirements before starting up a VM on the host. If the requirements are not met, the system migrates the VM to the optimal host to start up. This function takes effect only when automatic migration is enabled for VMs.

• Shared Storage Overcommitment Limit: Select whether to enable shared storage overcommitment limit. With this feature disabled, shared storage overcommitment is not limited. As a best practice, enable this feature for critical services. With this feature enabled, you can set the shared storage overcommitment ratio. If you do not enable this feature, monitor the shared storage pool usage. When the shared storage pool usage is high, scale up the pool or delete unnecessary files to avoid read/write service interruption.

Customization Parameters

• System Name: Enter a name for the CAS system.

• Copyright Info: Enter the copyright information on the login page.

• Homepage Logo: Enter the path where the homepage logo is saved. The logo is displayed on the top left of the homepage.

• Login Page Logo: Enter the path where the login page logo is saved.

• Homepage Tiny Logo: Enter the path where the small size homepage logo is saved. The logo is displayed on the top left of the homepage when the navigation tree is collapsed.

• Favicon: Enter the path where the favicon is saved.

• Copyright Logo: Enter the path where the copyright logo is saved.

• Login Page Background: Enter the path where the login page background is saved.

Customized Menu Parameters

• Menu Name: Enter the name of the system to be accessed from CVM.

• Menu URL: Enter the URL for accessing the system.

VNC Proxy Server Parameters

• Server IP: Enter the IP address of the VNC proxy server.

• Username: Enter the username used to access the VNC proxy server.

• Password: Enter the password for the user to access the VNC proxy server.

• VNC Console Password: Specify the password used to connect to the VNC consoles of VMs. This password takes effect only on VMs that are created after the password configuration. To change the VNC console password of a specific VM, access the VM editing page.

• VNC Password: Select whether to use VNC random password for the VMs. After you enable this feature, the configured VNC passwords become invalid.

DNS Server Parameters

• DNS Server: Enter a maximum of three semicolon-separated DNS server IP addresses for CVM. This setting takes effect on all hosts on CVM.

HA Parameters

·          Use the default settings for the HA system as long as possible. The stability of CAS might degrade if a too large or too small value is set. ·          Do not change the default HA settings for initial deployment. To change the HA settings for temporary use, evaluate your configuration first and make sure you understand the impact of the change on services. To change HA settings for long time use, contact technical support to evaluate the impact on services.

 

• Host Heartbeat: Specify the interval at which CVK hosts send heartbeat packets to CVM. If a CVK host fails, the heartbeat is interrupted, and VMs on the host are migrated to other hosts in the same cluster after three host heartbeat intervals and three storage heartbeat intervals.

• Storage Heartbeat: Specify the interval at which CVK writes timestamps to the storage pool. If a storage network fails, the heartbeat is interrupted, and affected VMs are migrated to other hosts in the same cluster after three storage heartbeat intervals.

Image Cleanup

• Max Usage (%): Specify the threshold for triggering image cleanup.

When the space usage of /vms/nova exceeds the maximum usage threshold, the system cleans up the cached images in this path until the space is larger than the reserved space or smaller than the specified space usage after cleanup.

• Reserved Space: Specify the space that must be reserved after image cleanup.

• Usage After Cleanup: Specify the maximum space usage after image cleanup.

CPU and memory

• Reserve Host Memory: Configure whether to reserve host memory. If you select Yes, the system reserves 20% of the host memory or 10 GB host memory (whichever is smaller). The reserved memory of a host cannot be used for VMs started on or migrated to the VM.

• Memory Allocation Ratio for All VMs: Configure the maximum ratio of the memory allocated to all VMs to the total memory size of a host. The system identifies whether this ratio is reached when one of the following events occurs:

• A VM is created, deployed, or cloned.

• A VM is migrated manually or automatically by the HA or DRS feature.

• A VM is restored from the recycle bin.

• A VM is added by DRX.

• A VM is migrated to a host through cloud rainbow.

• CPU or memory allocation is edited for a VM.

• An OVF template is imported.

• A VM is restored from a snapshot or backup.

To ensure service continuity when the maximum memory allocation ratio is exceeded, DRX and VM migration by the HA or DRS feature will still run normally.

• Memory Allocation Ratio for Running VMs: Configure the maximum ratio of the memory allocated to running VMs to the total memory size of a host. The system identifies whether this ratio is reached when one of the following events occurs:

• A VM starts.

• CPU or memory allocation is edited for a running VM.

• A VM is restored from a memory snapshot.

• A running VM is migrated manually.

• A VM is migrated automatically by DRS.

• A VM is added by DRX.

• A VM is migrated to a host through cloud rainbow.

To ensure service continuity when the maximum memory allocation ratio is exceeded, DRX and VM migration by the HA or DRS feature will still run normally.

• CPU Overcommit: Select whether to enable CPU overcommitment. Options include Yes and No. If you select Yes, the number of vCPUs bound to the physical CPUs of a NUMA node can exceed the number of the physical CPUs. If you select No, the number of vCPUs bound to the physical CPUs of a NUMA node cannot exceed the number of the physical CPUs.

• CPU Allocation Ratio for All VMs: Configure the maximum ratio of the CPUs allocated to all VMs to the total number of CPUs on a host. The system identifies whether this ratio is reached when one of the following events occurs:

• A VM is created, deployed, or cloned.

• A VM is migrated manually or automatically by the HA or DRS feature.

• A VM is restored from the recycle bin.

• A VM is added by DRX.

• A VM is migrated to a host through cloud rainbow.

• CPU or memory allocation is edited for a VM.

• An OVF template is imported.

• A VM is restored from a snapshot or backup.

To ensure service continuity when the maximum CPU allocation ratio is exceeded, DRX and VM migration by the HA or DRS feature will still run normally.

• CPU Allocation Ratio for Running VMs: Configure the maximum ratio of the CPUs allocated to running VMs to the total number of CPUs on a host. The system identifies whether this ratio is reached when one of the following events occurs:

• A VM starts.

• CPU or memory allocation is edited for a running VM.

• A VM is restored from a memory snapshot.

• A running VM is migrated manually.

• A VM is migrated automatically by DRS.

• A VM is added by DRX.

• A VM is migrated to a host through cloud rainbow.

To ensure service continuity when the maximum CPU allocation ratio is exceeded, DRX and VM migration by the HA or DRS feature will still run normally.

Upgrade

• Graceful VM Shutdown Period (Seconds): Configure this parameter for the system to wait for a specific period of time to allow VMs to shut down before host upgrade. This practice can avoid data loss or service interruption.

• Graceful Host Recovery Period (Seconds): Configure this parameter for the system to wait for a specific period of time to all a host to restart successfully and restore to normal state. This practice ensures that the host has completed the upgrade and is running stably before continuing to run VMs. This parameter takes effect only when a restart is required in host upgrade.