This article is intended to help determine the quantity and size of disks required on the Docker host dedicated to the Legacy Orchestrator. To meet the full engineering specifications, the following disk configurations are required for Docker hosts supporting 5K, 15K, 30K, or 60K profiles.
Deployment Profile Sizing
The following table outlines the required free space on the root partition and specifies the number of additional data disks needed, based on different performance metrics and element counts.
| Profile Name | Element Count | Performance Session Count1 | Enable RTD2 Metrics | Root Partition Free Space3 (GB) | Number of Additional Data Disks | Additional Data Disk Size (GB) |
|---|---|---|---|---|---|---|
| 5K | 100 | 1,000 | No | 91 | 0 | - |
| 5K | 100 | 1,000 | Yes | 94 | 0 | - |
| 5K | 100 | 52,000 | No | 397 | 0 | - |
| 5K | 100 | 52,000 | Yes | 553 | 0 | - |
| 5K | 100 | 125,000 | No | 835 | 0 | - |
| 5K | 100 | 125,000 | Yes | 1220 | 0 | - |
| 5K | 5,000 | 20,000 | No | 285 | 0 | - |
| 5K | 5,000 | 20,000 | Yes | 365 | 0 | - |
| 5K | 5,000 | 52,000 | No | 477 | 0 | - |
| 5K | 5,000 | 52,000 | Yes | 633 | 0 | - |
| 5K | 5,000 | 125,000 | No | 915 | 0 | - |
| 5K | 5,000 | 125,000 | Yes | 1300 | 0 | - |
| 15K | 15,000 | 0 | - | 65 | 1 | 750 (Disk for mediation1 and 2) |
| 15K | 15,000 | 20,000 | No | 65 | 1 | 870 (Disk for mediation1 and 2) |
| 15K | 15,000 | 20,000 | Yes | 65 | 1 | 930 (Disk for mediation1 and 2) |
| 15K | 15,000 | 125,000 | No | 65 | 1 | 1145 (Disk for mediation1 and 2) |
| 15K | 15,000 | 125,000 | Yes | 65 | 1 | 1530 (Disk for mediation1 and 2) |
| 30K | 30,000 | 0 | - | 65 | 2 | 750 (Disk for mediation1) 750 (Disk for mediation2 and 3) |
| 30K | 30,000 | 20,000 | No | 65 | 2 | 870 (Disk for mediation1) 750 (Disk for mediation2 and 3) |
| 30K | 30,000 | 20,000 | Yes | 65 | 2 | 930 (Disk for mediation1) 750 (Disk for mediation2 and 3) |
| 60K | 60,000 | 0 | - | 65 | 4 | 750 (Disk for mediation1) 750 (Disk for mediation2 and 3) 750 (Disk for mediation4) 750 (Disk for mediation5 and 6) |
| 60K | 60,000 | 20,000 | No | 65 | 4 | 870 (Disk for mediation1) 750 (Disk for mediation2 and 3) 750 (Disk for mediation4) 750 (Disk for mediation5 and 6) |
| 60K | 60,000 | 20,000 | Yes | 65 | 4 | 930 (Disk for mediation1) 750 (Disk for mediation2 and 3) 750 (Disk for mediation4) 750 (Disk for mediation5 and 6) |
1 Assuming 1 week of retention.
2 RTD is Round trip delay
3Assuming the default directory of Docker images is /var/lib/docker (on the root partition) - using the same disk with the OS of Docker host.
Separate Partition for Docker Host
If the Docker host uses separate partitions for system directories, ensure the locations listed below meet the following minimum free space requirements. These are mandatory for the Legacy Orchestrator to function correctly.
| Location | Directory / Docker Volume | Minimum Free Space (GB) | Description |
|---|---|---|---|
| Temporary storage | /tmp |
15 | Used for temporary application files during the installation process; can be redirected if needed |
| Docker images | /var/lib/docker |
30 | Used for the Docker storage (images, containers, etc.) |
| The skylight user home (/home/skylight) | /home |
20 | Used for the skylight user home (excluding application logs and database space if they are not on separate partitions) |
| Application logs | so-logs | 7 | Default:
|
| Database | so-mysql | 28 | Used for application database Default: |
| Application data | so-data so-data-mednXinstance (X is a mediation number from 2-6) |
Variable | Used for application data Refer to the sizing table below for specific requirements. |
Notes:
- Verification: Use the command
df -h /path/folder/locationto confirm the available space on the specific partition where the directory (location) is mounted. - Shared Partitions: If multiple locations (e.g., /home, /home/skylight/so/logs) reside on the same partition, that partition must have a total free space equal to the sum of the requirements for all directories located within it.
- Refer to Docker CLI Reference for more details on configuring logs, mysql, and data(s) locations.
| Profile Name | Element Count | Performance Session Count | Enable RTD Metrics | Free Space for Data Location | Number of Additional Data Disks (GB) | Additional Data Disk Size (GB) |
|---|---|---|---|---|---|---|
| 5K | 100 | 1,000 | No | 26 | 0 | - |
| 5K | 100 | 1,000 | Yes | 29 | 0 | - |
| 5K | 100 | 52,000 | No | 332 | 0 | - |
| 5K | 100 | 52,000 | Yes | 488 | 0 | - |
| 5K | 100 | 125,000 | No | 770 | 0 | - |
| 5K | 100 | 125,000 | Yes | 1155 | 0 | - |
| 5K | 5,000 | 20,000 | No | 220 | 0 | - |
| 5K | 5,000 | 20,000 | Yes | 300 | 0 | - |
| 5K | 5,000 | 52,000 | No | 412 | 0 | - |
| 5K | 5,000 | 52,000 | Yes | 568 | 0 | - |
| 5K | 5,000 | 125,000 | No | 850 | 0 | - |
| 5K | 5,000 | 125,000 | Yes | 1235 | 0 | - |
| 15K | 15,000 | 0 | - | - | 1 | 750 (Disk for mediation1 and 2) |
| 15K | 15,000 | 20,000 | No | - | 1 | 870 (Disk for mediation1 and 2) |
| 15K | 15,000 | 20,000 | Yes | - | 1 | 930 (Disk for mediation1 and 2) |
| 15K | 15,000 | 125,000 | No | - | 1 | 1145 (Disk for mediation1 and 2) |
| 15K | 15,000 | 125,000 | Yes | - | 1 | 1530 (Disk for mediation1 and 2) |
| 30K | 30,000 | 0 | - | - | 2 | 750 (Disk for mediation1) 750 (Disk for mediation2 and 3) |
| 30K | 30,000 | 20,000 | No | - | 2 | 870 (Disk for mediation1) 750 (Disk for mediation2 and 3) |
| 30K | 30,000 | 20,000 | Yes | - | 2 | 930 (Disk for mediation1) 750 (Disk for mediation2 and 3) |
| 60K | 60,000 | 0 | - | - | 4 | 750 (Disk for mediation1) 750 (Disk for mediation2 and 3) 750 (Disk for mediation4) 750 (Disk for mediation5 and 6) |
| 60K | 60,000 | 20,000 | No | - | 4 | 870 (Disk for mediation1) 750 (Disk for mediation2 and 3) 750 (Disk for mediation4) 750 (Disk for mediation5 and 6) |
| 60K | 60,000 | 20,000 | Yes | - | 4 | 930 (Disk for mediation1) 750 (Disk for mediation2 and 3) 750 (Disk for mediation4) 750 (Disk for mediation5 and 6) |
Scaling and Performance Logic
Selecting a deployment profile that scales beyond 5,000 network elements requires that operators configure Legacy Orchestrator Docker with data disks. This is needed to ensure sufficient disk space and I/O performance is available to the application.
Out of the box, the Legacy Orchestrator Docker ships with its OS disk configured with the 5K profile. This profile starts up a single process called a mediation instance that is responsible for network element communications, as well as performance data collection. These operations are disk I/O intensive.
- Whereas the 5K profile uses a single mediation instance, the 15K, 30K and 60K deployment profiles use a total of two (2), three (3), and six (6) mediation instances, respectively. Each mediation instance is assigned a work area under the data volume directory.
In order to spread the load, it is recommend that each data disk is assigned to three mediation instances. This means that the 15K profile requires one (1) data disk, 30K profile requires two (2) data disks, and the 60K profile requires four (4) data disks.
Disk Configuration for the 5K Profile
As per the table above, the Legacy Orchestrator application can run with a single disk (the same disk with OS of Docker host) when using the 5K profile. The required size of the disk is impacted by:
- The number of Provider Connectivity Assurance devices you need to manage
- The number of performance sessions you plan to add to the system
- The frequency of your performance sessions
- The retention period of your sessions.
CAUTION: If the retention period and disk size are configured improperly, the OS disk will fill up. If the issue is not corrected before a disk full condition, performance data collection will be impacted and historical data may be lost.
The default Legacy Orchestrator application requires 65 GB of disk space (this includes disk space for Docker images, database, application log files, etc.) to work properly.
If configuration of 1,000 performance sessions and adding 100 network elements is needed, the Administrator must ensure the disk size of Docker host satisfies to allot for:
- 20 GiB per slice of 1,000 Provider Connectivity Assurance devices
- At least one slice must be budgeted for when going beyond 100 Provider Connectivity Assurance Sensors or 1,000 performance sessions.
- 6 GiB per slice of 1,000 performance sessions with Round trip delay mode disabled.
- Sessions are configured at one-minute intervals.
- Sessions are configured for a one-week retention period.
- This rule can be applied linearly. If you are running the 1,000 sessions at five-minute intervals, you only require 1.2 GiB of disk space per week.
- 9 GiB per slice of 1,000 performance sessions with Round trip delay mode enabled.
- Sessions are configured at one-minute intervals.
- Sessions are configured for a one-week retention period.
- This rule can be applied linearly. If you are running the 1,000 sessions at five-minute intervals, you only require 1.8 GiB of disk space per week.
For example, if configuration to run 52,000 performance sessions on the system with less than 1,000 Provider Connectivity Assurance devices (the minimum allotted for Provider Connectivity Assurance devices) is needed, the free disk size necessary for Docker host:
- 20 GB for the Provider Connectivity Assurance devices
- 312 GB for the performance sessions (assuming one week retention).
312 + 20 + 65 = 397 GB.
Disk Configuration for the 15K Profile
The 15K profile requires the addition of one 750 GB disk to the Docker host which deployed the Legacy Orchestrator.
It is highly recommended to split out this new disk onto a distinct physical drive or drive array, as it will need to sustain up to 15K disk I/O operations per second, with an average block size of 6 KiB, and an average latency of 5 ms. Failure to meet these specifications will lead to application down time.
Note: Ensure that one additional disk added to the Docker host is configured and mounted under the directory mount point before assigning the profile for the Legacy Orchestrator Docker.
In order to spread the load, it is recommended that each data disk be assigned to three mediation instances. This means that the 15K profile requires one (1) data disk and it is assigned to:
- Two (2) mediation instances with Legacy Orchestrator Docker
For instructions on how to configure mediation volumes, refer to Assigning the Deployment Profile.
Disk Configuration for the 30K Profile
The 30K profile requires the addition of two 750 GB disks to the Docker host which deployed the Legacy Orchestrator. This is done by creating two new hard disks in the hypervisor and assigning these disks to the Docker host.
It is highly recommended to split out this new disk onto a distinct physical drive or drive array, as it will need to sustain up to 15K disk I/O operations per second, with an average block size of 6 KiB, and an average latency of 5 ms. Failure to meet these specifications will lead to application down time.
Note: Ensure that two additional disks added to the Docker host are configured and mounted under the directory mount point before assigning the profile for the Legacy Orchestrator Docker.
In order to spread the load, it is recommended that each data disk be assigned to three mediation instances. This means that the 30K profile requires two (2) data disks and it is assigned to:
- Three (3) mediation instances with Legacy Orchestrator Docker
For instructions on how to configure mediation volumes, refer to Assigning the Deployment Profile.
Disk Configuration for the 60K Profile
The 60K profile requires the addition of four 750 GB disks to the Docker host which deployed the Legacy Orchestrator. This is done by creating two new hard disks in the hypervisor and assigning these disks to the Docker host.
It is highly recommended to split out this new disk onto a distinct physical drive or drive array, as it will need to sustain up to 15K disk I/O operations per second, with an average block size of 6 KiB, and an average latency of 5 ms. Failure to meet these specifications will lead to application down time.
Note: Ensure that four additional disks added to the Docker host are configured and mounted under the directory mount point before assigning the profile for the Legacy Orchestrator Docker.
In order to spread the load, it is recommended that each data disk be assigned to three mediation instances. This means that the 60K profile requires four (4) data disks and it is assigned to
- Six (6) mediation instances with Legacy Orchestrator Docker
For instructions on how to configure mediation volumes, refer to Assigning the Deployment Profile.
For specific deployment considerations, see Docker Environment Guidelines in the Release Notes.
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