Overview
If it looks like the Code42 agent is restarting your backup unexpectedly, it may actually be running a file verification scan. The scan is an important and normal part of the Code42 agent's scheduled activities, but it can also be triggered by several events. This article describes:
- Events that trigger the scan
- How to verify whether or not files are backing up for the first time (restarting your backup)
- Where to find solutions for issues with the file verification scan
File verification scan
The file verification scan inspects your file selection for any new, changed, or deleted files that real-time file watching may have missed. Think of it as a second line of defense for detecting changes to your backup file selection.
If the file verification scan is in process when a backup status report is sent, the backup status report may reflect the percentage of your file selection that has been verified instead of the amount backed up. You can verify the actual size of your backup archive using Option 1 below.
Diagnosing
There are several items you can check to verify that your backup archive is intact and that the Code42 agent is not starting your backup over.
Option 1: Verify the size of your archive
Verify that the amount of data being stored is a number that is consistent with your file selection size and previous backup completion.
- Open the Code42 agent.
- Select
Settings.
- Click Destinations.
- From the list of destinations, select the one containing the archive you are verifying.
- Verify that the Space used is an amount of data reasonable for your file selection size and previous backup completion.
Option 2: Review history for scan
To confirm that the verification scan is running, you can check the History in the Code42 agent.
- Go to History.
- Windows: Tools > History
- Mac: Windows > History
- Linux: Tools > History
- Determine if a file verification scan is running. The messages below are typical of a scan running:
06/14/13 03:00AM [Default] Scanning for files to back up 06/14/13 03:00AM [Default] Stopped backup to CrashPlan Central in 4.5 hours 06/14/13 03:00AM - Reason for stopping backup: Full filesystem scan started. 06/14/13 03:06AM [Default] Scanning for files completed in 6 minutes: 110,368 files (157.40GB) found
Option 3: Review effective speed of your backup
Another indication that the Code42 agent is running the file verification scan - not backing up files - is an effective rate that is significantly higher than the sent rate.
- Navigate to History.
- Windows: Tools > History
- Mac: Windows > History
- Linux: Tools > History
- Compare the effective rate and the sent rate. Look for a line like this (sent and effective rates are shown in bold for this example):
I 02/09/14 12:45PM [Default] Stopped backup to CrashPlan PRO Online in 15 minutes: 439 files (558.10MB) backed up, 24.50MB encrypted and sent @ 86.2Kbps (Effective rate: 6.1Mbps)
In this case, the effective rate is 6.1 Mbps while the sent rate is only 86.2 Kbps. You may notice discrepancies that are even larger than this.
When the file verification scan is running, the effective rate is much higher than the sent rate because it takes into account the de-duplication of the data that's already been sent. When the Code42 agent comes to a file in the to-do list that's already backed up, it adds the size of the file to the amount of data its completed during that backup. It does this even though it didn't actually send anything.
Option 4: Review your logs
Using the backup_files.log file, you can definitively identify whether or not a file is backing up for the first time. The first two numbers summarize the Code42 agent's analysis of the file:
Recommended solution
Scan working as expected
If you determine that the file verification scan is running, and that it is only detecting a minor amount of changes that the real-time file watcher may have missed, give the scan time to complete. You can still download files while the scan is running, if necessary. If the Code42 agent is synchronizing, you can't download from the app, but you can perform a web restore.
The most likely explanation relates to how the Code42 agent prioritizes files for backup. The Code42 agent backs up your most recent changes first. When the scan finds new files for backup, these files go straight to the top of the “to-do” list. This impacts the estimated time to complete backup because the estimate is based on the type of files the scan is reviewing, new or existing) and your current network speed.
As these new or newly modified files complete backup, the Code42 agent moves on to your already-backed-up files. At that point, the effective transfer rate rises dramatically because the Code42 agent sends significantly less data to your backup destinations for previously-backed up files. This is data de-duplication in action. For more information, see our article on How backup works.
Scan not working as expected
- File verification is running: If the scan detected a unexpectedly large amount of changes that need to be backed up, it could indicate there is a problem with your file verification scan schedule that is preventing changes from being detected on a regular basis.
- File verification scan is not running: If the Code42 agent is backing up files that were previously backed up and treating them like new files, contact your administrator.