We use cookies on our website to ensure we provide you with the best experience on our website. By using our website, you agree to the use of cookies for analytics and personalized content.This website uses cookies. More Information
It seems like your browser didn't download the required fonts. Please revise your security settings and try again.
Barracuda CloudGen Firewall

This Firmware Version Is End-Of-Support

Documentation for this product is no longer updated. Please see https://campus.barracuda.com/doc/71862301/ for further information on our EoS policy.

How to Use the Grey Listing Tab

  • Last updated on

Contents of the Grey Listing tab are associated with Grey Listing set to enabled in the Mail Gateway settings (Section Grey Listing, see: How to Configure Content Stripping, Grey Listing, and Blacklists). The list summarizes e-mail delivery attempts, which have reached the gateway. The Grey Listing tab is subdivided into two areas, a Grey List and a White List.

Grey List

Data sets in the Grey List are arranged in sections disclosing the e-mails' arrival time. E-mails are classified into the following categories: 

  • Newer than 1 hour
  • Between 1 and 12 hours
  • Older than 12 hours 

Objects in the first category Newer than 1 hour are subject to a greater movement. Sender-recipient pairs are removed from the grey list with the following successful delivery attempt. E-mails which do not experience a second delivery attempt, are successively moved to the lower categories. The grey list can be used to: 

  • Recognize peers exclusively delivering junk mail. When known, these hosts can be added to the IP Blacklist in the Block Filter configuration section (see above section Blacklists, IP Blacklist) thus further reducing unwanted e-mail traffic.
  • Recognize uncritical sender-recipient pairs whose e-mails could not be delivered due to a misconfigured sender's mail server not attempting a second delivery attempt. When known, these senders and/or hosts can be added to the White List Peers and/or Senders fields in the Grey Listing configuration section (see above section Grey Listing, White List Peers/Senders) thus excluding the specific servers from Grey Listing. 

Available information is arranged in the following columns: 

  • Sender – Shows the sender’s e-mail address.
  • Receiver – Shows the recipient’s e-mail address.
  • Peer IP – Shows the IP address of the sending mail server.
  • Peer Hostname – Shows the delivering mail server’s hostname, if its name is DNS resolvable. Otherwise the field will contain the string unknown.
  • Count - This is the number of counted delivery attempts. Multiple unsuccessful delivery attempts might occur when the sending mail server retries delivery before Grey Listing Time expiration (see Grey Listing Time (Min)).
  • First Try – This is the time of the first delivery attempt.
  • Last Try – This is the time of the last delivery attempt.
  • All Tries – This is the sum of all delivery attempts. Multiple delivery tries may possibly occur, if successive delivery attempts under-run the Grey Listing Time (Min)

Grey Listing entries older than 12 hours are automatically deleted after 1 day.

White List

Contents of the White List are associated with parameter Auto White List (Senders) set to yes in the Mail Gateway Settings (Section Grey Listing, see: How to Configure Content Stripping, Grey Listing, and Blacklists). The list contains all e-mail senders whose e-mails have been delivered successfully and which have been added to the temporary White List automatically. Available information is arranged in the following columns: 

  • Sender – Shows the sender’s e-mail address.
  • Listed Since – Shows the date when the e-mail address has been added to the White List.

Context Menu Entries

Data sets in the White List are deleted automatically according to the interval, which is defined through parameter Remove from White List after (d) (see above section). Manual deletion is possible through the following context menu entries available through right clicking any data set: 

  • Remove – Deletes the selected entry from the list.
  • Clear List – Deletes all entries from the list. 

Continue with: Logs, Statistics, Events.

Last updated on