QoreStor 6.1.0 - User Guide

Streams and connections

This topic describes the differences between data streams and application connections.

Streams refer to the number of files written at the same time to QoreStor. QoreStor tracks the number of files being written and assembles the data into 4–MB chunks before processing that section of the data. If the stream count is exceeded, the data is processed out of order and overall deduplication savings can be affected.

Connections are created by applications; and, within a single connection, there can be multiple streams depending on the application and the number backup jobs running in parallel over that single connection.

Quotas

QoreStor provides the option to configure quotas for Storage Groups and Performance Tiers. With quotas, you can define a limit for physical capacity usage. Upon reaching that limit, data ingests to that storage group or performance tier will be disallowed until sufficient space is recovered through cleaner operations.

Before considering implementing quotas, please take into account these limitations and recommendations:

• Quotas are not set by default.
• The minimum quota value is 100 GiB.
• Once set, quotas can be reduced, but cannot be set below the storage group's used capacity.
• For standard storage groups, the maximum quota value is restricted to the current physical capacity of the QoreStor system.
  • For performance tiers, the maximum quota value is restricted to the the size of the performance tier filesystem.

Secure connect

Secure Connect encompasses a set of client and server components that creates a secure channel for QoreStor communication with WAN-connected clients that is also resilient to WAN outages.

Secure Connect uses the TLS 1.2 standard with a 4096-bit RSA key. Certificates are created automatically for both client and server, but you can use you own certificates if you chose.  When using Secure Connect (which is enabled by default when using the latest QoreStor and plug-in versions), the client opens a connection to the QoreStor server over port 9443. The client sends the actual QoreStor port number to the server, which then opens a local connection to that port enabling secure communication with the client. Configuration of Secure Connect ports is done through the client and server configuration file. See Configuring Secure Connect for more information.

Secure Connect also provides a method for resilient WAN connections. Packets processed by Secure Connect clients are assigned a unique identifier and are assigned to a temporary cache before being sent to the QoreStor server. When the packet is successfully delivered to the QoreStor Secure Connect server, the packet identifier is marked as delivered and acknowledged to the Secure Connect client. If the WAN connection is lost, the client and server both continue to cache data packets. When the connection is restored, unacknowledged packets are re-sent and properly processed, avoiding data loss and process interruption.

MultiConnect

QoreStor MultiConnect establishes multiple connections between RDA and OST clients and the QoreStor server. On high-bandwidth networks, these connections can improve backup and replication performance. To obtain the most benefit from MultiConnect, both MultiConnect and SecureConnect should be enabled. Refer to the sections below:

• Enabling Secure Connect
• Enabling MultiConnect