A Basic Computer Data Backup Option for Solo or Small-firm Attorneys: Areca Review

Several months ago, I embarked on what I thought would be the easy task of finding a simple, usable, and effective computer data backup solution for my solo attorney law practice. I was wrong; I seriously underestimated the [needless] complexity of this task (even with my technology background). While backup solutions abound, I struggled to find a solution that met basic criteria. I provide this article to hopefully help other Pennsylvania lawyers evaluating backup options.

Basic Backup Software Criteria

When considering a backup for my law firm data, my criteria were:

  • ability to truly encrypt the backup data using a key that I control and with industry recognized encryption technology (e.g., AES);
  • simple installation and updates of the backup software;
  • reasonable licensing fee (considering a small firm);
  • ability to backup to a basic, external hard drive;
  • ability to specify the data to be included in the backup (no “auto” backups that might miss data or that might store unnecessary data);
  • ability to change the backup set (files targeted for backup) as needs change (e.g., folders move);
  • ability to log and review the backup process;
  • ability to compress backups [to save space];
  • ability to see the file names stored in the backup;
  • simple restore process including partial restores and restoration to a different location;
  • robust backup engine that allows, at minimum, full and incremental backups (and ability to switch between the two); and
  • preferably no backup server or “agent” running in the background.

Many of the items specified are obvious best practices. Nevertheless, I found that most backup offerings failed to meet the major criteria. Licensing fees were an issue in some cases. Vendors apparently see two types of customer: 1) the home user backing up personal photos or 2) General Motors-class businesses with complex networks and deep pockets. Unfortunately, many of the home user backup solutions specifically prohibit any commercial use (read the license carefully).

While the list of criteria above should alone be helpful, the following explanations of some of my criteria may help lawyers who are unfamiliar with backups. Each item listed provides more detail about why a criterion is on the list.

Encryption of the Backup Data

A primary criterion was the ability to encrypt the backup using industry accepted encryption technology and a key that I control. Many lawyers might miss this important criterion. Since my backups include client information (normally stored in encrypted volumes on my hard drive), the backup also should maintain similar encrypted protection of the data. Some backup solutions, however, merely copy files to the backup location (or use pseudo-encryption based on a “password” and unclear encryption method). I sought a solution that uses standard encryption technology, like AES, with a key that I specify (so I control who unlocks the data). [FN1]

Ability to Specify and Change Backup Sets

Generally, you should be able to define a backup set by selecting specific folders, subfolders, or files for backup. While automatic backups offered by some vendors might sound easier, these solutions might over-include or under-include. Over-inclusion increases backup size and backup time—not to mention potentially saves significant amounts of unnecessary data. Under-inclusion can also occur with some automatic backups because some of these solutions only backup common file types such as PDFs, JPGs (photos), or DOCs (word processing). These solutions might miss important specialized files such as Outlook EML, OST ,or PST (email) files; OpenDocument (ODT) files; or accounting files.
Furthermore, the ability to change the backup set locations allows you to organize your files and then simply update the backup set—without needing to re-create the entire backup.

Full, Differential and Incremental Backup Capability

Essentially, backups use three types of scope: 1) full, 2) incremental, and 3) differential. The first two are essential for backup efficiency. Distinguishing the roles of each type is important to assure adequate backup coverage and efficient restoration.

  • Full backups copy every file and folder defined in the backup set regardless of changes. Generally, full backups occur on a regular basis and act as a complete, stand alone backup.
  • Differential backups copy ONLY files changed since the last full backup (and always look to the last full backup and not interim incremental backups). The advantage of differential backups is evident during restoration after a disaster. Generally when using differential backups, one must restore the last full backup (all files) and then only the last differential backup (any changes since the full backup). The disadvantage of differential backups is size and time to complete.
  • Incremental backups copy ONLY files changed since the last incremental backup (or if no prior incremental backup, then since the last full backup). Think of an incremental backup as ONLY CHANGES and only changes since the last INCREMENTAL BACKUP. This creates a daisy-chain effect. Unlike a differential backup, in the event of a disaster and need to recover, the last full backup must be restored then EVERY incremental backup since the last full backup must be restored in EXACT order. While incremental backups are faster and save space, relying on them alone can be false economy in the event of a disaster—recovering a full backup and six months worth of incremental backups, one at a time, is tedious and prone to error. Thus, generally, incremental backups are best as interim (short term) backups between regular full backups.

Generally, one might run a full backup on a monthly basis with differential backups weekly and incremental backups daily. (Check the internet for best practices with backup schemes or consult an experienced, technology professional.)

Why is knowing the difference between backup types important? From a backup perspective, the importance is modest—usually limited to backup time and backup size. Generally, one balances efficiency (time to backup) and backup size/resource use (disk space). While running a full backup every time is conceivable, such a methodology will quickly fill-up disk space and every backup may take quite some time to complete. Running less frequent, full backups with frequent incremental backups may save time with each backup and reduce overall disk space use. The key is balancing full with incremental (or differential) backups.

However, the real issue is from the restoration perspective (after a disaster or after a inadvertent file deletion). As noted above, relying on incremental backups for lengthy periods creates a serious problem with restoring the backup because EVERY incremental backup must be applied (and in proper order) to assure a complete backup restoration.[FN2]

Tools for Checking Backups

Several of the criteria listed facilitate validation of the backups. Logs summarizing the files backed-up, backup manifests, and ability to see file names in the backup all help to validate the backup. Even with logs and manifests, however, you should test (actually restore a file from the backup) on a regular basis to further validate the effectiveness of the backup.

Backup Solution Selected: Open Source Areca

Areca (http://www.areca-backup.org/)
After assessing over a dozen backup options (and weeding out even more), the backup solution that met my criteria was Areca—an open source project released under GPL2. I have been using the application for several months and am happy with the performance and capabilities. Areca provides native AES encryption, on-the-fly compression, backup-set management, manifest/log files, multiple backup-set definitions, full/incremental/differential backups, and broad backup target support (USB drives, external hard drives, FTP, etc.).

The Areca development team provides a suitable tutorial and user manual describing the features. Essentially, you simply specify a Backup Target (the device where you want the backup to reside) and then define the Backup Set Parameters (encryption, files/folders to include, files to exclude, compression (zip)). Areca uses the term Workspace to describe the the combination of the Backup Target and the Backup Set Parameters. Once setup, Areca saves your configuration. Subsequent backups simply require attaching the target drive, opening Areca, clicking the WorkSpace, and selecting Backup. The Backup option lets you further select full, differential, or incremental backups as necessary. The encryption and compression occur automatically (once configured).

While the Areca user interface is somewhat spartan, functionally the interface provides easy access to the archives, logs, progress report, and restore options. Restoring items merely takes pointing-and-clicking. Restoring to an alternate restore location (a folder different from the original folder location) is also possible.

As open source software, the user community supports the product—there is no direct support telephone number. Email and online support forums list solutions to common problems. Also as open source software, Areca does not require a licensing fee, although voluntary contributions are encouraged.

Areca runs on Windows and Linux. [FN3] Download Areca at http://www.areca-backup.org/.


As indicated, I initially thought that finding a solid backup solution would be easy. While many options are available, most did not meet my core requirements. A reviewer must be cautious when evaluating options (some packages seem to meet the criteria) and must carefully read the licenses (commercial products, such as those included on external hard drives, may be home-use-only licensing). Using a poor backup solution (such as not being able to easily update backup sets or to specify multiple backup types) may lead to frustration and disuse. Areca, for me, seems to meet or exceed my needs—simple and effective.


FN1—Note: even if you use Bitlocker, TrueCrypt, or similar encryption on your hard drive, when the files are copied to the backup drive, the encryption might be lost because these solutions encrypt within the volume but not necessarily at the file level. Be careful. The backup software should copy the files from the encrypted volume and should then apply encryption to the backup copy to assure the files remain encrypted in storage.

FN2— Backup Illustration
Assume a quarterly backup plan:
Full backup—April 1

Incremental backups
April Week 1, April Week 2, April Week 3, April Week 4
May Week 1, May Week 2, May Week 3, May Week 4
June Week 1, June Week 2, June Week 3, June Week 4

Now, assume that a catastrophic failure on June 30 requiring a complete restore of all data. Using this plan, a complete restore requires:
Restore the Full Backup from April 1. Then tediously restore EACH incremental backup in order:
April Week 1, April Week 2, April Week 3, April Week 4,
May Week 1, May Week 2, May Week 3, May Week 4,
June Week 1, June Week 2, June Week 3, and June Week 4.
This illustration shows the danger of relying on only incremental backups as the primary backup methodology. Restoring three months worth of incremental backups is a tedious and time consuming task.

FN3—The support site hints that Areca might work on Mac/Apple OSX although direct support on the Areca website is not clear.

Original Publication Date

23 May 2011
Minor editorial revisions: 09 June 2011