Uses for External Dynamic Lists in Policy
| Where Can I Use This? | What Do I Need? |
|---|
- NGFW (Cloud Managed)
- NGFW (PAN-OS & Panorama Managed)
- Prisma Access (Managed by Strata Cloud Manager)
- Prisma Access (Managed by Panorama)
| Check for any license or role requirements for the products you're using. |
An External Dynamic List is a text file that is hosted on an external web server so that
your configuration can import objects—IP addresses, URLs, and domains. Additionally for
PAN-OS & Panorama, International Mobile Equipment Identities (IMEIs) and
International Mobile Subscriber Identities (IMSIs)—included in the list and enforce
policy. To enforce Security policy on the entries included in the external dynamic list,
you must reference the list in a supported security rule or profile. When multiple lists
are referenced, you can prioritize the order of evaluation to make sure the most
important EDLs are committed before capacity limits are reached. As you modify the list,
the list dynamically imported at the configured interval and enforces policy without the
need to make a configuration change or a commit. If the web server is unreachable, the
last successfully retrieved list is used for enforcing policy until the connection is
restored with the web server. In cases where authentication to the EDL fails, the
Security policy stops enforcing the EDL. To retrieve the external dynamic list, the
interface configured with the Palo Alto Networks Services service
route is used.
Your configuration retains the last successfully retrieved EDL and continues operating
with the most current EDL information until connection is restored with the server
hosting the EDL if:
- You upgrade or downgrade your environment
- You reboot your environment, management plane, or data plane
- The server hosting the EDL becomes unreachable
These types of external dynamic lists are supported:
Predefined IP Address—A predefined IP address list is a type of IP address
list that refers to the built-in, dynamic IP lists with fixed or “predefined”
contents. These
Configure Your Environment to Access an External Dynamic List—for bulletproof hosting providers,
known malicious, and high-risk IP addresses—are automatically added to your
configuration if you have an active Threat Prevention license. A predefined IP
address list can also refer to an EDL that uses one of the built-in lists as a
source. Because you can’t modify the contents of a predefined list, you can use
a predefined list as a source for a different EDL if you want to add or exclude
list entries.
- Predefined URL List—This type of external dynamic list
contains pre-populated URLs that applications use for background services, such as
updates or Certificate Revocation List (CRL) checks, that can safely be excluded
from Authentication policy. Palo Alto Networks revises and maintains this type of
external dynamic list, which is also known as an Authentication Portal Exclude List,
through content updates.
IP Address—Your environment typically enforces policy for a source or
destination IP address that is defined as a static object on the device (see
Enforce Policy on an External
Dynamic List). If you need agility in enforcing policy for a list of
source or destination IP addresses that emerge ad hoc, you can use an external
dynamic list of type IP address as a source or destination address object in
security rules, deny or allow access to the IP addresses (IPv4 and IPv6 address,
IP range and IP subnets) included in the list. You can also use an IP address
EDL in the source or destination of an SD-WAN security rule. An external dynamic
list of type IP address is treated as an address object; all the IP addresses
included in a list are handled as one address object.
Domain—This type of external dynamic list allows you to import custom
domain names to enforce policy using an Anti-Spyware profile or SD-WAN policy
rule. An EDL in an Anti-Spyware profile is very useful if you subscribe to
third-party threat intelligence feeds and want to protect your network from new
sources of threat or malware as soon as you learn of a malicious domain. For
each domain you include in the external dynamic list, a custom DNS-based spyware
signature is created so that you can enable DNS sinkholing. The DNS-based
spyware signature is of type spyware with medium severity and each signature is
named
Custom Malicious DNS Query <domain
name>. You can choose to include the subdomains of a
specifed domain. For example, if your domain list includes paloaltonetworks.com,
all lower level components of the domain name (e.g., *.paloaltonetworks.com)
will also be included as part of the list. When this setting is enabled, each
domain in a given list requires an additional entry, effectively doubling the
number of entries used by the list. For details on configuring domain lists, see
configure DNS sinkholing for a custom list of
domains.
URL—This type of external dynamic list gives you the agility to protect
your network from new sources of threat or malware. An external dynamic list
with URLs are handled like a custom URL category and you can use this list in
two ways:
As a match criterion in Security rules, Decryption security rules,
and QoS security rules to allow, deny, decrypt, not decrypt, or allocate
bandwidth for the URLs in the custom category.
(PAN-OS & Panorama Only) Equipment Identity—You can reference
an external dynamic list of IoT devices defined by International Mobile
Equipment Identities (IMEIs) in a Security rule that controls traffic for
equipment connected to a 5G or 4G network. Refer to the Mobile Network
Infrastructure Getting Started for information about configuring Equipment ID
security on supported device models.
(PAN-OS & Panorama Only) Subscriber Identity—You can
reference an external dynamic list of International Mobile Subscriber Identities
(IMSIs) in a Security rule that controls traffic for subscribers
connected to a 5G or 4G network. Refer to the Mobile Network Infrastructure
Getting Started for information about configuring Subscriber ID security on
supported device models.
(
PAN-OS & Panorama Only) On each device model, you can add up to a maximum
of 30 custom EDLs with unique sources that can be used
to enforce policy. The external dynamic list
limit is not applicable to Panorama. When using Panorama to manage a device that is
enabled for multiple virtual systems, if you exceed the limit for the device, a commit
error displays on Panorama. A source is a URL that includes the IP address or hostname,
the path, and the filename for the external dynamic list. The device matches the URL
(complete string) to determine whether a source is unique.
While the device does not impose a limit on the number of lists of a specific type, the
following limits are enforced:
IP address—The PA-3200 Series, PA-5200 Series, and the PA-7000 Series devices
support a maximum of 150,000 total IP addresses; all other models support a
maximum of 50,000 total IP addresses. No limits are enforced for the number of
IP addresses per list. When the maximum supported IP address limit is reached,
the a syslog message is generated. The IP addresses in predefined IP address
lists do not count toward the limit.
URL and domain—The maximum number of URLs and domains supported varies by model.
No limits are enforced for the number of URL or domain entries per list. Refer
to the following table for specifics on your model:
|
Model
| URL List Entry Limits | Domain List Entry Limits |
PA-5200 Series, PA-5400 Series, PA-7000 Series
(upgraded with the PA-7000 20GXM NPC, PA-7000 20GQXM NPC, or the
PA-7000 100G NPC).
PA-7000 appliances with mixed NPCs only support the
standard capacities. | 250,000 | 4,000,000 |
|
VM-500, VM-700
|
100,000
| 2,000,000 |
|
PA-400 Series (excepting the PA-410), PA-850, PA-820, PA-3200
Series, PA-3400 Series
|
100,000
| 1,000,000 |
|
|
PA-220, PA-410, VM-50, VM-50 (Lite), VM-100, VM-1000-HV
|
50,000
| 50,000 |
List entries only count toward the limits if they belong to an external dynamic list that
is referenced in policy.
- (Panorama Only) When parsing the list, entries that do not match the
list type are skipped, and ignores entries that exceed the maximum number
supported for the model. To ensure that the entries do not exceed the limit,
check the number of entries currently used in policy. Select and click List Capacities.
An external dynamic list must contain entries. If you want to stop using the
list, remove the reference from the security rule or profile instead leaving
the list blank. If the list does not contain any entries, the list can't be
refreshed and so the last information retrieved is used.
As a best practice, Palo Alto Networks recommends using shared EDLs when
multiple virtual systems are used. Using individual EDLs with duplicate
entries for each virtual system uses more memory, which might over-utilize
device resources.
EDL entry counts on devices operating multi-virtual systems take additional
factors into account (such as DAGs, number of virtual systems, rules bases)
to generate a more accurate capacity consumption listing. This might result
in a discrepancy in capacity usage after upgrading from PAN-OS 8.x
releases.
Depending on the enabled features, memory usage limits might be exceeded
before EDL capacity limits are met due to memory allocation updates. As a
best practice, Palo Alto Networks recommends reviewing EDL capacities and,
when necessary, removing or consolidating EDLs into shared lists to minimize
memory usage.
Monitoring External Dynamic List Policy Enforcement
After configuring external dynamic lists in your security policy rules, you can monitor and
verify that traffic matching EDL entries is being handled according to your policy by
filtering logs based on the action taken. Use log filters to view specific actions on
traffic that matched your EDL-based rules.
To filter logs based on actions taken on EDL-related traffic:
Navigate to (or Threat, URL Filtering, or other log types depending on your use
case).
Use the filter bar to enter a query with the action parameter. Common filter
examples include:
