StorMagic Glossary of terms

Hyperconverged infrastructure (HCI) combines servers and storage into a distributed infrastructure platform with intelligent software. This creates flexible building blocks that replace legacy infrastructure consisting of separate servers, storage networks, and storage arrays.

Software-defined refers to a hardware or service component that is improved or completely managed by software. Activities traditionally done by hardware are carried out by software, which operates independently from the hardware and can be updated by the provider.

Each system is allocated a unique serial number, which is used together with the license key when licensing SvSAN features.

SvSAN and SvKMS are licensable products, each requiring a license key to operate. References:

• SvSAN Licensing model
• SvSAN Online and Offline Licensing
• SvKMS Licensing

StorMagic offers both perpetual and subscription licenses. Perpetual is typically a higher up-front capex cost and continues operating, with maintenance associated. Subscription is time-based opex with an ongoing cost model.

Software typically has a version associated with it, representing a specific build. As infrastructure software, customers do not typically upgrade like a phone app. Upgrades are non-disruptive and typically related to:

• Hardware refresh
• Firmware/drivers in the StorMagic software
• Hypervisor or ecosystem versions a release has been tested or certified against

Some StorMagic software products operate in a dual-boot model, allowing selection of a prior version to back out an upgrade, although this is rarely needed.

Firmware is programming written to a hardware device’s non-volatile memory, which is retained without power. StorMagic OS runs either as a guest VM, storage controller VM on a hypervisor, or on hardware as a RAM disk with a persistent scratch partition for logging. This results in a .img firmware file that can be pushed to the appliance or node into the dual-boot partition for non-disruptive upgrades.

StorMagic software includes a maintenance mode where certain services are stopped while the node remains manageable.

SvSAN uses StorMagic Discovery Protocol, or discovery, so systems such as appliances, VSAs, witnesses, and other hosts can discover each other on an IP network. Each system is assigned a unique discovery ID. Discovered information includes hostname, system type, discovery ID, interface IPs, and system status.

Discovery runs on Windows and Linux, on VSAs and witnesses. By default it uses IP multicast UDP to multicast address 239.255.23.23 and port 4174, which is registered with IANA. Systems announce every 5 minutes and on status or configuration change. Entries not heard from for 5 days are purged, except static entries.

If multicast is blocked, such as gateways not forwarding multicast, discovery supports manual entries using direct UDP requests and static entries for NAT or cloud-hosted witness scenarios. If a remote system cannot be found, discovery falls back to DNS. Large environments can be grouped by SAN name so only matching SAN names discover each other.

Reference: Discovery documentation

Automatic entries are picked up via multicast within an IP subnet. Static entries can be added when multicast is blocked or systems, such as a witness, are in another subnet or behind NAT.

• SAN name for cluster
• SvSAN and SAN Names
• Configuring a SAN name

iSCSI transports SCSI commands and data over TCP/IP Ethernet connections. It is an open standard, documented in standards including RFC3720. iSCSI uses Ethernet and TCP/IP as transport, standard authentication such as CHAP, and may use other protocols such as iSNS for discovery.

SvSAN provides storage as virtual disks presented to hosts as SCSI target devices over iSCSI. From a SCSI perspective, the virtual disk is the logical unit of the SCSI target, LUN 0, similar to disk drive models.

Target properties can include:

• Logical unit number, always 0
• Globally unique 64-bit SCSI identifier, EUI-64, shown as hexadecimal
• Capacity / size

Initiators log in using their IQN, but other software, such as multipathing, may operate at the SCSI layer and use the EUI-64. In the UI, iSCSI targets and their LUN are commonly referred to simply as targets.

One of the two sides of a mirrored target.

If mirror plexes go offline or the network between them fails, an isolation policy is applied to prevent data corruption. SvSAN supports two mirror isolation policies: Majority and Up.

• Majority: relies on a third-party quorum system, the Witness Service, running on a separate system such as a witness appliance VM, Windows server, another VSA, or Linux host.
• Up: used when only two physical servers exist and no witness placement is possible. It handles common failures but may require user intervention in some scenarios.

Cache is a high-speed data storage layer storing a subset of data, often transient, so future requests are served faster than accessing primary storage.

A local path locates a file on your system. Multipath enhances fault tolerance and load balancing by distributing traffic across multiple paths, allowing data transfer through alternate routes if one fails.

The Events log lists significant events on the system, most recent first. There are three types:

• Error: a fault that must be rectified, and the most severe.
• Warning: unexpected event that should be checked.
• Informational: normal operations, such as start/stop or target created/deleted.

An initiator is a device or program that starts a task or sends data to a storage array using iSCSI, Fibre Channel, or SCSI sessions.

Types:

• iSCSI initiator: software or hardware that sends data to or from iSCSI storage
• SCSI initiator: device that sends SCSI commands to start a SCSI session
• Fibre Channel initiator: device that originates Fibre Channel sessions

Each iSCSI element, initiator or target, has a unique iSCSI name called an iSCSI Qualified Name, or IQN. The IQN is a logical name and is not linked to an IP address.

A storage pool is a collection of devices grouped into a single logical pool. A pool can only be created from devices connected to the same physical storage hardware.

A disk stores data. HDDs are non-volatile storage devices, retaining data even when power is not supplied.

Software RAID is managed by the operating system, not a dedicated controller. JBOD, Just a Bunch Of Disks, stores data on individual drives. RAID stores data across multiple drives for improved performance and/or redundancy.

JBOD

• Simplicity: easy to manage and expand
• Cost: less expensive than RAID
• Redundancy: none, meaning disk failure loses data on that disk
• Use cases: non-critical storage, such as archiving

RAID

• Performance: better than JBOD
• Data protection: protects against disk failure, depending on RAID level
• Requires more planning, such as drive sizing and proactive maintenance

The maximum combined storage capacity you can allocate, or license, across all pools on the VSA, except SSD cache pools, which are exempt. This figure, or unlimited, is set by the VSA license and may be distributed across multiple pools.

A journaling file system tracks changes by recording them in a separate log or journal. After failure or crash, it helps restore the data pre-failure and recover unsaved data to the intended destination.

Rescanning storage updates storage and pool information to keep management in sync with underlying infrastructure.

Common reasons to rescan:

• After creating or deleting snapshots manually
• After changes to physical disks or disk groups
• To discover new paths or re-acquire lost paths
• To search for new tape libraries or stand-alone tape drives

What rescan does:

• Updates storage hierarchy
• Ensures management sees up-to-date pool information
• Keeps management in sync with physical infrastructure
• Causes virtual disk paths to appear or disappear
• Discovers new paths or re-acquires lost paths

The current configuration or condition of a system/device at a given time, including relevant data or variables defining its condition.

A device is online when powered on and connected to a network, other devices, or the internet. If you cannot access sites or email, you may be offline. If only one site is unavailable, that server may be offline.

Synchronization coordinates processes or ensures multiple copies of data are consistent and up to date.

Why it matters:

• Data integrity
• Collaboration across devices
• Backups

Unsynchronized data is not aligned or up to date, such as data that is not saved or copied elsewhere. This may occur if signal or coverage is weak or unreliable.

Storage degraded means the system is still functioning but with reduced performance due to one or more component failures, often a failed disk, while still allowing access to data, commonly seen in RAID scenarios.

Storage failure means a storage device can no longer function properly due to physical damage, logical errors, or server-side issues.

Signs can include:

• Sudden performance changes
• High read/write error counts
• Crashes, especially if it is the boot drive
• Drive unresponsiveness

• In flight: protects data as it moves through the network by encrypting before transport and decrypting by the authorized receiver.
• At rest: protects stored data using encryption algorithms. Data is only decrypted with the appropriate key, which is useful if a device is lost or stolen.

An encryption certificate is a digital file containing a public key used to encrypt data, such as files, documents, emails, or data transmissions.

Common uses:

• Establish session keys for encryption and decryption
• Confirm secure communication, so only the intended recipient can decrypt
• Validate websites and establish secure connections with SSL/TLS

Types:

• SSL/TLS certificates
• S/MIME certificates
• Wildcard SSL certificates for a base domain and subdomains

P6R, Project 6 Research, provides encryption/key management solutions, including ChaCha20Poly1305 and a KMIP Server Gateway, or KSG.

ChaCha20Poly1305:

• Cipher suite providing encryption and message authentication
• Recommended by IETF for TLS
• Efficient across many hardware types, including embedded and mobile
• Can encrypt and authenticate multiple messages simultaneously
• Resistant to nonce misuse

KMIP Server Gateway, KSG:

• Manages crypto key storage
• Can be bundled with an HSM
• Integrates apps requiring the OASIS KMIP protocol

Cryptsoft encryption technology supports secure storage and distribution of encryption keys to protect data.

• StorMagic Product Documentation
• SvSAN Licensing model
• SvKMS Licensing