Registry configuration

ExchangeMode

N/A

N/A

N/A

This value is set when Email Gateway Security is installed in Exchange plugin mode. For details see Integrations/Onsite Microsoft Exchange deployment.

Do not change this value manually!

InstallationFolder

C:\Program Files\OPSWAT\MetaDefender Email Security\

string

N/A

This value is by the Email Gateway Security installation.

Do not change this value manually!

external_quarantine_block

dword

optional

Enable quarantining the original copy of blocked emails on an other mail server. For details see Configuration/Quarantine configuration.

If the parameter does not exist or if it is 0, then the internal quarantine will be used in case of blocked emails.

external_quarantine_sanitize

dword

optional

Enable quarantining the original copy of sanitized emails on an other mail server. For details see Configuration/Quarantine configuration.

If the parameter does not exist or if it is 0, then the internal quarantine will be used in case of sanitized emails.

sender_helo_domain

computer name

string

optional

The fully qualified domain name (FQDN) that Email Gateway Security will send in HELO/EHLO commands to relay SMTP servers to customize SMTP greetings. Besides this FQDN the external IP address of Email Security will also be sent. For details see section Opening and closing in RFC 821.

If the parameter does not exist or if it is empty then the computer name of Email Gateway Security is sent in HELO/EHLO.

receiver_helo_domain

computer name

string

optional

The fully qualified domain name (FQDN) that Email Gateway Security will send in HELO/EHLO commands to SMTP clients to customize SMTP greetings. For details see section Opening and closing in RFC 821.

If the parameter does not exist or if it is empty then the computer name of Email Gateway Security is sent in the response to a HELO/EHLO.

exchange_exclude_probe_emails

dword

optional

Microsoft Exchange Server sends probe email messages to monitor the health status of the email processing components. This probe messages can, however, fill Operating/Email History. Setting this parameter to 0 will enable listing Exchange probe messages in Audit > Email History.

If the parameter does not exist or if it is 1, then Exchange probe messages are not listed in Audit > Email History_____ ** __ ** ** ** _ __ . No service restart is needed There is no need to restart any services for this setting to take effect, because the transport agent reads and applies this registry setting for each email.

processing_threshold

75

dword

optional

This parameter limits the number of emails with "Processing" status at the same time. If this parameter is not present then this number is 75 by default. Setting this value lower can reduce the processing load on both Email Gateway Security and Core.

If the parameter is 0 then the throttling is disabled.

concurrency_threshold

N/A

dword

optional

This parameter limits the number of concurrent threads submitting emails to MetaDefender Core for scanning. Example By default Email Gateway Security submits emails to Core on several threads. This causes the components of different emails to mix in the Core queue.

If this parameter is set to 1, then contents are sent to Core email by email with no overlapping, whereas If the parameter is 0 then no direct limitation is applied.

scheduled_db_optimization_time

03:00

string

optional

If this parameter is set, then Email Gateway Security performs a database optimization at the time configured.

The DB optimization time must be set in 24 hours scheme.

Syntax: <hh>:<mm>

If not set (or an invalid value is provided), no optimization is performed.

in_folder_timer_interval

1000

dword

optional

Interval –in milliseconds– between polling of new emails.

max_email_insert_count

100

dword

optional

Maximum number of emails to insert into the database in a single batch.

processing_task_timeout

10

string

optional

The email processing task timeout (in minutes). If this timer elapses, Email Gateway Security will give up trying to process the email.

restaddress

string

required

One or all of the IP addresses of the computer that runs the product to serve the web user interface.

Supported value: * : all IPv4 and IPv6 interfaces One specific IPv4 or IPv6 address : the specific IPv4 or IPv6 address

(* = all interfaces)

restport

8058

string

required

Designated port number for the web management console (REST) interface

public_rescan_port

N/A

string

optional

Designated port number for the rescan functionality web and REST interface.

Rescan functionality is always -even if this value is defined- available on the restport. For details about rescan__see Operating/Password protected attachments.

smtpaddress

string

optional

One or all of the IP addresses of the computer that runs the product to serve the SMTP interface (* means all interfaces)

Supported values Missing or * : all IPv4 and IPv6 interfaces One specific IPv4 or IPv6 address : the specific IPv4 or IPv6 address

public_id_length

32

string

optional

Length of id generated for public rescan links. Allowed values are 32-64.

logfile

string

optional

Location of a log file to write log messages to. If the parameter does not exist, then no logs are written to any logfile.

Empty string is not allowed as a value.

loglevel

string

optional

Level of logging. Supported values are: debug, info, warning, error, soc.

wineventlog_level

info

string

optional

Level of logging. Supported values are: debug, info, warning, error, soc. If the parameter does not exist, then no logs are written to the Windows Logs.

syslog

string

optional

Value can only be in form of udp://<hostname>:<port>. If the parameter does not exist, then no logs are written to syslog. (Multiple server can be specified separated with comma)

syslog_level

string

optional

Level of logging. Supported values are: debug, info, warning, error, soc.

override

string

optional

Override specific log ids to display them on another level e.g.: "1723:error,663:info". Note: when displaying these log ids their original level will remain the same.

Empty string is allowed as a value.

cef

false

string

optional

If true, the log format is Common Event Format.

local_timezone

false

string

optional

If true, the times sent in syslog messages will be in the server's local time zone. This does not effect entries in the log file/Windows event log. When syslog is used with cef and local_timezone enabled the time zone name can vary based on the underlying system and it's settings. Examples

• Syslog

  • UTC: 2018-09-19T13:07:36Z

  • Local: 2018-09-19T15:07:36+02:00

• Syslog with CEF

  • UTC: Sep 19 13:12:47 UTC

  • Local 1: Sep 19 15:12:47 CEST

  • Local 2: Sep 19 15:12:47 Central Europe Daylight Time

nginx_logfile

[installdir]\nginx \nginx.log

string

optional

File name and path to store the Nginx logs.

log_rotation

false

string

optional

If true, the log file specified by the logfile entry is rotated after 24 hours from creation.

The last 30 log files are stored, the oldest log file will be deleted if number of files reaches the limit. The logfile entry must be set for this option to work.

The rotated log files are named according to the following convention: <file name from logfile entry>-<yyyyMMdd>-<nnn>.gz The trailing three digits (<nnn>) ensure that the file name is unique.

Example: mdemailsecurity-20200525.gz

All stored log files are included in MetaDefender Email Gateway Security's support package.

nginx_log_rotation

false

string

optional

If true, the log file specified by the nginx_logfile entry is rotated after 24 hours from creation.

The last 30 log files are stored, the oldest log file will be deleted if number of files reaches the limit.

The rotated log files are named according to the following convention: <file name from nginx_logfile entry>-<yyyyMMdd>-<nnn>.gz The trailing three digits (<nnn>) ensure that the file name is unique.

Example nginx-20200730.gz

All stored Nginx log files are included in MetaDefender Email Gateway Security's support package.

instance

computer name

string

required

This parameter is the name of the Email Gateway Security instance in scalable mode. This parameter is relevant when upgrading a standalone instance to scalable.

For details see Operating/Scalable deployment operation.

mode

local

string

required

This parameter tells Email Gateway Security in what scalability mode it is. This parameter must be local for bundle and standalone edition deployments.

For details see Operating/Scalable deployment operation.

enable_chunking_support

0

string

optional

Set to 1 to enable SMTP server BDAT verb. For details, see RFC 3030

monitor_server_name

localhost

string

optional

Override the server name used when monitoring the MetaDefender Email Gateway Security's inbound SMTP server. This might be required when TLS is used and the certificate subject lacks localhost entry.

antispam_proxy_ip

N/A

string

optional

IP address of the HTTP proxy to reach the anti-spam service. For details about the location of the anti-spam service see Prerequisites/External services.

antispam_proxy_port

N/A

string

optional

TCP port of the HTTP proxy to reach the anti-spam service. For details about the location of the anti-spam service see Prerequisites/External services.

quarantine_report_hourly_minute

00

string

optional

The minute in each hour when hourly quarantine reports are to be assembled and sent. The valid range is 00-59. For details about quarantine reports see Quarantine reports.

quarantine_report_daily_time

12:00 (midday)

string

optional

The time on each day when daily quarantine reports are to be assembled and sent. The valid range is 00:00-23:59. For details about quarantine reports see Quarantine reports.

hsts_max_age

31536000 (1 year)

string

optional

HTTP Strict-Transport-Security response header (HSTS) max age value in seconds.

html_prioritize_header_charset

0

dword

optional

Set to 1 to prioritize header charset for HTML body content (instead of <meta> charset tag).

scan_tnef

1

dword

optional

Set to 0 to prevent sending unparsed TNEF (winmail.dat) for scanning

add_scan_headers

0

dword

optional

Set to 1 to prevent Email Gateway Security adding any diagnostics headers to inbound emails.

ignore_certificate_revocation_list

0

dword

optional

Set to 1 to skip certificate revocation lists when validating certificates

spf_dns_servers

N/A

multi-string

optional

List of DNS servers to be used by Sender Policy Framework (SPF) component

domain_lookup_level

N/A

string

optional

This option controls whether Email Gateway Security should perform a reverse DNS lookup on the sending IP address as an anti-phishing measure.

When enabled, in case the sending IP address does not belong to a domain (any domain), the email can be classified as Possible phishing or Phishing based on the value of this option. Supported values:

• disabled: reverse DNS lookup not performed

• possible phishing: reverse DNS lookup performed, and if no domain is returned then the email is classified as Possible phishing and handled according to the Potential Phishing settings

• phishing: reverse DNS lookup performed, and if no domain is returned then the email is classified as Phishing and handled according to the Known Phishing settings

The reverse DNS lookup uses the DNS server that is set in the spf_dns_serversoption abpve.

For details about classifications see Email classifications.

For details about handling Potential Phishing and Known Phishing see Anti-phishing and anti-spam.

dkim_phishing_verdicts

• Invalid

multi-string

optional

This option configures what DKIM verification results will result in the email being classified as Phishing and handled according to the Known Phishing settings. The available results are:

• No signature

• Invalid

• Error

For details about classifications see Email classifications.

For details about handling Potential Phishing and Known Phishing see Anti-phishing and anti-spam.

dkim_possible_phishing_verdicts

N/A

multi-string

optional

This option configures what DKIM verification results will result in the email being classified as Possible phishing and handled according to the Potential Phishing settings.

The available results are:

• No signature

• Invalid

• Error

For details about classifications see Email classifications.

For details about handling Potential Phishing and Known Phishing see Anti-phishing and anti-spam.

spf_phishing_verdicts

• Fail

• Soft fail

multi-string

optional

This option configures what SPF check results will result in the email being classified as Phishing and handled according to the Known Phishing settings. The available results are:

• No record

• Neutral

• Soft fail

• Fail

• Error

For details about classifications see Email classifications.

For details about handling Potential Phishing and Known Phishing see Anti-phishing and anti-spam.

spf_possible_phishing_verdicts

N/A

multi-string

optional

This option configures what SPF check results will result in the email being classified as Possible phishing and handled according to the Potential Phishing settings.

The available results are:

• No record

• Neutral

• Soft fail

• Fail

• Error

For details about classifications see Email classifications.

For details about handling Potential Phishing and Known Phishing see Anti-phishing and anti-spam.