When selecting the number of disks for a video server, consider the archive depth required, i.e. how many disks will be needed to store the total volume of data.
The required number of disks is always calculated based on the total data stream. The size of the stream ("bitrate") depends directly on a number of factors, including: the number of cameras, picture resolution, number of recorded frames per second, compression codec used by an IP camera or video capture card, etc. In a running system you can check the total rate on the channels tab. In order to calculate the capacity of disks and their number, you can use the calculator on our website.
Table 1.
| Number of disks | Rate for upgrade from versions 2 and 3 (fragmented disks) | Rate for formatted disks |
|---|---|---|
| 1 | 5 MB/s | 50 MB/s |
| 2 | 7 MB/s | 50 MB/s |
| 3 | 15 MB/s | 100 MB/s |
| 4 | 20 MB/s | 150 MB/s |
| 5+ | 25 MB/s | 200 MB/s |
Tip
You can check the list of recommended for use HDDs in our knowledge base.
When using network storage devices, keep in mind that:
- It may take up to 20 minutes to connect certain iSCSI drives after losing a connection for more than one minute due to outages in the local network.
- When using RAID arrays (for example, RAID5), if one of the disks fails, the data transmission rate will drop by more than a factor of two.
Important
To optimize hard disk use and ensure maximum speed for archive recording, the size of the hard disks' logical partitions must not vary by more than a factor of 2.
For example, if you use a local disk with a logical partition of 1 TB in a video recorder, when a new hard disk is installed to the server or when network storage is connected to the TRASSIR server, the logical partitions on them must not exceed 2 TB.
