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Understanding Backup Bandwidth UsageYou can monitor a computer's bandwidth usage to see how much bandwidth is being used over time to back up the computer's files. What is backup bandwidth usage?Backup bandwidth usage is the amount of upstream bandwidth that LiveVault Online Backup Service uses to send the changed files from your computer to the backup server. Because LiveVault Online Backup Service uses upstream bandwidth for backup, it generally does not disrupt your downstream bandwidth activities such as Web browsing. For backup to succeed, your available upstream bandwidth must support the amount of data that is being backed up at the rate that data is changing. By default, LiveVault Online Backup Service will use as much available network bandwidth as it needs to back up your data, up to a maximum of 6 megabytes per second (6 MBps). However, you need to consider a computer's bandwidth usage in relation to the computer's backup latency. If the computer's backup latency is high, then you should analyze the computer's bandwidth usage. If the backup latency is reasonable, then you can generally assume that the computer's bandwidth usage is not a concern. Bandwidth usage guidelinesBandwidth usage varies with different types of data and data change rates. Initial synchronizationDuring a computer's initial synchronization, you will see higher bandwidth usage as the files are replicated in full for the first time. Data transfer rates for the initial synchronization can be estimated at 2 GB per day for each 256 Kbps of available bandwidth. However, the data transfer rate may improve by as much as 50% when a few large files, as opposed to an equivalent number amount of data consisting of many smaller files, are being protected. Typically, if only the minimum bandwidth is available for the given capacity, it could take nine days or more to complete the initial synchronization. It is recommended that you have enough bandwidth to complete the initial synchronization for any single large file in five days or fewer. After initial synchronization completes, the bandwidth usage will decrease, as only changes are backed up. Ongoing protectionA good rule of thumb based upon a typical 5% daily change rate, is that LiveVault Online Backup Service uses about 20 kilobits per second of your bandwidth for every gigabyte being backed up. The following table lists common bandwidths and estimates of the amount of backed up data they can support, assuming a 5% average daily change rate. These are conservative estimates, based upon one server being backed up using a single connection; it is possible that multiple servers sharing that single connection may be able to back up more data across that same connection.
Backing up highly dynamic servers such as mail servers and high-activity database servers may mean higher change rates that require additional bandwidth. Higher rates of change result in a linear increase in required bandwidth. Note: LiveVault Online Backup Service does not measure bandwidth capacity. Many Internet connections are advertised by their downstream bandwidth. Make sure you know your upstream bandwidth. It is also important that if you are using DSL that you have SDSL (Synchronous Digital Subscriber Line) and not ADSL (Asynchronous Digital Subscriber Line), which may not have enough upstream bandwidth. We recommend contacting Customer Service if you have questions about bandwidth usage. Interpreting the Bandwidth Usage chartUse the 24 hour or 7 day outbound Bandwidth Usage charts in MyLiveVault to identify how much data is changing and when. Based on the speed of your Internet connection, use the Bandwidth Usage chart to determine how much of your bandwidth is being used to back up that data. This can be particularly important if you have a lot of data that changes frequently and limited available bandwidth. Also, as the amount of data being backed up grows over time, it may also help you determine whether a faster Internet connection may be necessary to back up all your critical data. The chart graphs the bandwidth usage for the backup configuration where:
Note: The outbound bandwidth charts show the amount of data transferred from your Agent computer to the backup server, primarily showing data being backed up. However, you will also observe on the inbound bandwidth charts a minor amount of control data that is transferred during backup operations. The chart is updated with current data every 20 minutes. For example, you may see a Bandwidth Usage chart similar to the following:
This chart shows that the amount of data being backed up by this computer varied throughout this day. The data LiveVault Online Backup Service transfer activity spiked at 150 bits per second 21 hours ago and again at 100 bits per second about 16 hours ago. Otherwise the amount of data has ranged from about 50 bits per second to periods of inactivity. As shown on the chart, each of these spikes were short, with the bandwidth usage quickly dropping to a more continuous flow. Overall this indicates that this computer is not consuming large amounts of bandwidth for excessive periods of time. The available bandwidth appears to be adequate for the amount of data and the current data change rate. Addressing high bandwidth usageBandwidth usage is charted across the whole computer. It is not charted by individual backup configuration. However, depending on what data is being backed up at specific times (for example, if you are using scheduled backup), you may be able to determine which backup configuration is consuming your bandwidth and make adjustments as necessary. For example, if you find that your Files and Directories backup configuration is consuming an unexpectedly large amount of your bandwidth, you may want to analyze the files selected for backup to determine if the configuration is backing up files that should be excluded, such as temporary files. If you find that your network is too slow for other non-LiveVault Online Backup Service activities, you can use the Bandwidth Usage charts to determine which data is changing most frequently, and consider scheduling backup of that data to occur at specific times. While not necessary in most environments, you can limit the amount of bandwidth available to LiveVault Online Backup Service for backup of a particular computer. This limit is applied across all backup configurations on that computer; it cannot be applied to particular configurations nor does it affect restore operations. If you are concerned about excessive bandwidth usage, we strongly recommend contacting Customer Service for assistance in analyzing what is causing the bandwidth usage and determining the most appropriate course of action. Related InformationMonitoring Backup Bandwidth Usage |
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