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How can I update Clam Antivirus via the terminal?

I already have installed clamav, but I want to know how can I update the virus database.

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AFAIK, there is no need to use this command in Ubuntu, the clam virus database is automatically updated. If you execute it you'll get an error such as ERROR: /var/log/clamav/freshclam.log is locked by another process – medigeek Oct 8 '13 at 22:24
To force the daily update to happen on-demand, you can stop the service & update & then restart it: $ service clamav-freshclam stop and then: $ sudo freshclam and again, $ service clamav-freshclam start – michael_n Dec 16 '15 at 7:01

To update the ClamAV database do sudo freshclam.

       freshclam - update virus databases

       freshclam [options]

       freshclam is a virus database update tool for ClamAV.

For offline update, you can also directly download virus definition from database: main, daily and then put them into /var/lib/clamav (remove old files).

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Will this work for Zorin OS7 Ultimate users? Thanks – user267883 Apr 11 '14 at 15:33

Run sudo apt-get install clamav.

Once ClamAv is installed you can set up a script for right click virus scanning in Nautilus.

To update the virus database, open a terminal and enter the following command:

sudo freshclam

To automate this update you can set up a cron job. I'll show how to update the virus database every day at 8:57 AM. First, open the terminal and su to root.

sudo su

Now you need to modify the crontab for the root user.

crontab -e

This opens the root crontab file in the nano text editor. Add the following line

57 08 * * * freshclam

to the crontab and then hit Ctrl+X to exit. Answer yes when prompted to save the file.

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If you put it in the root crontab, you don't need sudo. – Pabi Nov 6 '14 at 8:53
Presently, the clamav-freshclam service takes care of updating the definitions (as of 15.04 for sure, possibly as early as 12.04). For Nautilus integration, install clamtk-nautilus (and restart nautilus) – michael_n Dec 16 '15 at 7:08

The right way to go is to edit freshclam.conf and add the number of dayly Checks you want

vim /etc/clamav/freshclam.conf
Checks 24
##Notify clamd to reload it self
NotifyClamd /etc/clamav/clamd.conf
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Wow! I was not aware that it would check once per hour by default! It seems like a lot to me... – Alexis Wilke Jan 28 at 7:28

How to update clamtk (all steps) / clamav (steps 1-3)

NOTE: Read each line before you willy nilly start typing things in Terminal to understand what you are doing to the system.

  1. Remove potentially bad AV installations:

    sudo apt-get remove clamav clamtk freshclam
    sudo apt-get autoremove
  2. Reinstall AV

    sudo apt-get install clamav -y      # *(Terminal Version)*
    sudo apt-get install clamtk -y      # *(GUI version)*
  3. Update AV Database

    sudo freshclam                    # *(takes ~30 minutes to download definitions)*
  4. Configure AV & Scan: This example uses only clamtk

    clamtk                           # (Opens GUI)*

    toggle all options beneath settings tab "Network"

    1. toggle "proxy" and type
    2. toggle / reselect "No Proxy" (to gray out #1 above)

    "Update Assistant"

    1. toggle "manual" update option and click apply and "back"
    2. toggle "automatic" update option and click apply and "back". You should now see updated definition count

    "Scan a Directory"

    1. toggle desired directory you want scanned. For system scan, I toggled the entire system (not just /root or /usr).
    2. Click scan and a progress box will appear.

Final Note: typing the phrase clamav --help gives some hints. -y is the same thing as saying yes to installing all dependencies for package. If -y causes issues then exclude and manually press y key when prompted.

This is what I had to do to get clam working, perhaps a glitch for both clamtk and clamav (problem with both). Hope this helps someone else!

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