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Documentation | Administration Manual | Reference Manual

Limits

The limits tab configures the limits and restrictions imposed on the reseller. Options include:

  • Maximum bit rate
    Specifies the maximum bit rate that this reseller can assign to each user account he creates. Note that this is a per-user limit, not a combined total.

  • Maximum accounts
    Specifies the maximum number of user accounts (streams) that the reseller can create.

    If the Unlimited checkbox is ticked, no account limit will be enforced for this account.

  • Listener slots (total)
    Specifies the total number of listeners this reseller can potentially host. This is a combined total limit for all user accounts created by this reseller. For example, if this value is set to 50, then the reseller could create two 25-listener streams, or he could create two 10-listener streams and one 30-listener stream, etc.

    If the Unlimited checkbox is ticked, no listener slot limit will be enforced for this account.

  • Disk quota
    Specifies the total amount of disk space allocated to this reseller. The reseller may assign this disk space to his user accounts as he sees fit, but the combined total of the disk space used by the reseller's user accounts will never be permitted to exceed this limit.

    If the Unlimited checkbox is ticked, no disk quota will be enforced for this account.

    If the Oversell checkbox is ticked, the reseller will be permitted to oversell his disk quota to his clients. See the Overselling section below for details.

  • Data transfer limit
    Specifies the maximum monthly data transfer limit for this reseller, in megabytes (MB). The reseller may assign data transfer limits to his user accounts as he sees fit, but the combined total of the data transfer used by the reseller's user accounts will never be permitted to exceed this limit.

    If the Unlimited checkbox is ticked, no data transfer limit will be enforced for this account.

    If the Oversell checkbox is ticked, the reseller will be permitted to oversell data transfer to his clients. See the Overselling section below for details.

  • Bandwidth limit
    Specifies the total amount of bandwidth (in kbps - NOT data transfer) which this reseller can allocate. This is an alternative to specifying a data transfer limit, and is simply an alternate way of imposing a similar restriction.

    For example, 10 listener slots at 128kbps would use 1280kbps of bandwidth (10 x 128 = 1280). Or, 5 slots at 128kbps and 8 slots at 64kbps would use 1152kbps of bandwidth (5 x 128 + 8 x 64 = 1152).

    If the Unlimited checkbox is ticked, no bandwidth limit will be enforced for this account.

    If you do not fully understand this metric, leave it set to "Unlimited" and assign a more conventional data transfer limit instead.

  • AutoDJ capabilities
    Specifies whether the reseller is permitted to assign autoDJ capabilities to his clients.

  • When transfer limit is exceeded
    Specifies the action to be taken when the reseller exceeds his data transfer limit. Options include:

    • Perform the default action - Performs the default action configured in the main Centova Cast settings
    • Suspend reseller - Suspends the reseller account and shuts down and suspends all of the reseller's clients' streams
    • Notify only - Notifies the reseller and administrator that the limit has been exceeded, but takes no other action
  • When disk quota is exceeded
    Specifies the action to be taken when the reseller exceeds his disk quota. Options include:

    • Perform the default action - Performs the default action configured in the main Centova Cast settings
    • Suspend reseller - Suspends the reseller account and shuts down and suspends all of the reseller's clients' streams
    • Notify only - Notifies the reseller and administrator that the limit has been exceeded, but takes no other action
  • Raw configuration
    Specifies whether the reseller is permitted to grant his clients access to their raw server and autoDJ configuration files. This is potentially a dangerous option and should only be enabled for trusted resellers.

  • Port 80 proxy
    Specifies whether the reseller is permitted to use Centova Cast's port 80 proxy. This option will only be displayed if the port 80 proxy has been enabled.

Overselling

Overselling refers to the practice of allocating to clients a greater amount of resources than are actually owned by the reseller. The underlying theory is that clients are unlikely to utilize their full resource allocations, and thus the reseller is able to more fully utilize his resources by distributing the unused portions to other clients.

When overselling is enabled for a resource, the reseller is permitted to allocate an arbitrary resource limit to his clients, possibly exceeding the value actually allocated to the reseller. The reseller is not penalized for this unless the sum of his clients' actual resource usage eventually exceeds the limit assigned to the reseller.

Example

In a traditional reselling scenario, a reseller may be assigned a 10GB disk quota. With this quota, the reseller might allocate his clients the following values:

User Quota
bob 5GB
tim 2.5GB
rob 2.5GB

This fully utilizes the reseller's 10GB quota, and the reseller is not permitted to allocate any further disk space to any new accounts. The problem with this scenario is that each of these clients is unlikely to fully utilize his entire disk quota. For example, after a month of use, the actual disk space used by these clients might be as follows:

User Quota Usage
bob 5GB 2.7GB
tim 2.5GB 1.0GB
rob 2.5GB 0.5GB

In this case, the reseller has allocated his entire 10GB quota, but his clients are only utilizing 2.7 + 1.0 + 0.5 = 4.2GB. The remaining 5.8GB of the reseller's disk quota is being wasted when it could, in theory, be resold to other clients.

Overselling attempts to accommodate this scenario by allowing the reseller to overallocate resources. The reseller's actual disk quota might only be 10GB, but what if -- through overselling -- he were permitted to allocate more than 10GB to his clients? Take this example:

User Quota Usage
bob 5GB 2.7GB
tim 2.5GB 1.0GB
rob 2.5GB 0.5GB
john 5GB 1.5GB
kate 3GB 1.0GB

In this case, the reseller has actually allocated 18GB of disk space -- 8GB greater than his disk quota -- but his clients are actually utilizing only 6.7GB -- still 3.3GB less than his disk quota. Because the amount of disk space actually used by his clients is still less than the reseller's disk quota, the reseller is not penalized for the overallocation.

Overselling does, however, present an inherit risk of resource exhaustion. In the above example, if john were to suddenly upload a large number of files and fully utilize his 5GB disk quota, the actual disk utilization for this reseller would total 10.2GB, exceeding the reseller's disk quota by 0.2GB. At that time, Centova Cast would enforce the "disk quota exceeded" action configured by the administrator for this reseller.