Maximum Segment Size (MSS)

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Maximum Segment Size (MSS)

Last Updated:

Feb 13, 2023

Current Version:

9.1

Version 10.1
Version 10.0 (EoL)
Version 9.1

Table of Contents

Filter

Getting Started

Integrate the Firewall into Your Management Network

Determine Your Management Strategy

Perform Initial Configuration

Set Up Network Access for External Services

Register the Firewall

Segment Your Network Using Interfaces and Zones

Network Segmentation for a Reduced Attack Surface

Configure Interfaces and Zones

Set Up a Basic Security Policy

Assess Network Traffic

Enable Free WildFire Forwarding

Best Practices for Completing the Firewall Deployment

Best Practices for Securing Administrative Access

Subscriptions

Subscriptions You Can Use With the Firewall

Activate Subscription Licenses

What Happens When Licenses Expire?

Enhanced Application Logs for Palo Alto Networks Cloud Services

Software and Content Updates

PAN-OS Software Updates

Dynamic Content Updates

Install Content Updates

Applications and Threats Content Updates

Deploy Applications and Threats Content Updates

Tips for Content Updates

Best Practices for Applications and Threats Content Updates

Best Practices for Content Updates—Mission-Critical

Best Practices for Content Updates—Security-First

Content Delivery Network Infrastructure

Firewall Administration

Management Interfaces

Use the Web Interface

Launch the Web Interface

Configure Banners, Message of the Day, and Logos

Use the Administrator Login Activity Indicators to Detect Account Misuse

Manage and Monitor Administrative Tasks

Commit, Validate, and Preview Firewall Configuration Changes

Export Configuration Table Data

Use Global Find to Search the Firewall or Panorama Management Server

Manage Locks for Restricting Configuration Changes

Manage Configuration Backups

Save and Export Firewall Configurations

Revert Firewall Configuration Changes

Manage Firewall Administrators

Administrative Role Types

Configure an Admin Role Profile

Administrative Authentication

Configure Administrative Accounts and Authentication

Configure a Firewall Administrator Account

Configure Local or External Authentication for Firewall Administrators

Configure Certificate-Based Administrator Authentication to the Web Interface

Configure SSH Key-Based Administrator Authentication to the CLI

Configure API Key Lifetime

Reference: Web Interface Administrator Access

Web Interface Access Privileges

Define Access to the Web Interface Tabs

Provide Granular Access to the Monitor Tab

Provide Granular Access to the Policy Tab

Provide Granular Access to the Objects Tab

Provide Granular Access to the Network Tab

Provide Granular Access to the Device Tab

Define User Privacy Settings in the Admin Role Profile

Restrict Administrator Access to Commit and Validate Functions

Provide Granular Access to Global Settings

Provide Granular Access to the Panorama Tab

Panorama Web Interface Access Privileges

Reference: Port Number Usage

Ports Used for Management Functions

Ports Used for HA

Ports Used for Panorama

Ports Used for GlobalProtect

Ports Used for User-ID

Reset the Firewall to Factory Default Settings

Bootstrap the Firewall

USB Flash Drive Support

Sample init-cfg.txt Files

Prepare a USB Flash Drive for Bootstrapping a Firewall

Bootstrap a Firewall Using a USB Flash Drive

Authentication

Authentication Types

External Authentication Services

Multi-Factor Authentication

SAML

Kerberos

TACACS+

RADIUS

LDAP

Local Authentication

Plan Your Authentication Deployment

Configure Multi-Factor Authentication

Configure MFA Between RSA SecurID and the Firewall

Configure MFA Between Okta and the Firewall

Configure MFA Between Duo and the Firewall

Configure SAML Authentication

Configure Kerberos Single Sign-On

Configure Kerberos Server Authentication

Configure TACACS+ Authentication

Configure RADIUS Authentication

Configure LDAP Authentication

Connection Timeouts for Authentication Servers

Guidelines for Setting Authentication Server Timeouts

Modify the PAN-OS Web Server Timeout

Modify the Captive Portal Session Timeout

Configure Local Database Authentication

Configure an Authentication Profile and Sequence

Test Authentication Server Connectivity

Authentication Policy

Authentication Timestamps

Configure Authentication Policy

Troubleshoot Authentication Issues

Certificate Management

Keys and Certificates

Default Trusted Certificate Authorities (CAs)

Certificate Revocation

Certificate Revocation List (CRL)

Online Certificate Status Protocol (OCSP)

Certificate Deployment

Set Up Verification for Certificate Revocation Status

Configure an OCSP Responder

Configure Revocation Status Verification of Certificates

Configure Revocation Status Verification of Certificates Used for SSL/TLS Decryption

Configure the Master Key

Obtain Certificates

Create a Self-Signed Root CA Certificate

Generate a Certificate

Import a Certificate and Private Key

Obtain a Certificate from an External CA

Deploy Certificates Using SCEP

Export a Certificate and Private Key

Configure a Certificate Profile

Configure an SSL/TLS Service Profile

Replace the Certificate for Inbound Management Traffic

Configure the Key Size for SSL Forward Proxy Server Certificates

Revoke and Renew Certificates

Revoke a Certificate

Renew a Certificate

Secure Keys with a Hardware Security Module

Set Up Connectivity with an HSM

Set Up Connectivity with a SafeNet Network HSM

Set Up Connectivity with an nCipher nShield Connect HSM

Encrypt a Master Key Using an HSM

Encrypt the Master Key

Refresh the Master Key Encryption

Store Private Keys on an HSM

Manage the HSM Deployment

High Availability

HA Overview

HA Concepts

HA Modes

HA Links and Backup Links

HA Ports on Palo Alto Networks Firewalls

Device Priority and Preemption

Failover

LACP and LLDP Pre-Negotiation for Active/Passive HA

Floating IP Address and Virtual MAC Address

ARP Load-Sharing

Route-Based Redundancy

HA Timers

Session Owner

Session Setup

NAT in Active/Active HA Mode

ECMP in Active/Active HA Mode

Set Up Active/Passive HA

Prerequisites for Active/Passive HA

Configuration Guidelines for Active/Passive HA

Configure Active/Passive HA

Define HA Failover Conditions

Verify Failover

Set Up Active/Active HA

Prerequisites for Active/Active HA

Configure Active/Active HA

Determine Your Active/Active Use Case

Use Case: Configure Active/Active HA with Route-Based Redundancy

Use Case: Configure Active/Active HA with Floating IP Addresses

Use Case: Configure Active/Active HA with ARP Load-Sharing

Use Case: Configure Active/Active HA with Floating IP Address Bound to Active-Primary Firewall

Use Case: Configure Active/Active HA with Source DIPP NAT Using Floating IP Addresses

Use Case: Configure Separate Source NAT IP Address Pools for Active/Active HA Firewalls

Use Case: Configure Active/Active HA for ARP Load-Sharing with Destination NAT

Use Case: Configure Active/Active HA for ARP Load-Sharing with Destination NAT in Layer 3

Refresh HA1 SSH Keys and Configure Key Options

HA Firewall States

Reference: HA Synchronization

What Settings Don’t Sync in Active/Passive HA?

What Settings Don’t Sync in Active/Active HA?

Synchronization of System Runtime Information

Monitoring

Use the Dashboard

Use the Application Command Center

ACC—First Look

ACC Tabs

ACC Widgets

Widget Descriptions

ACC Filters

Interact with the ACC

Use Case: ACC—Path of Information Discovery

Use the App Scope Reports

Summary Report

Change Monitor Report

Threat Monitor Report

Threat Map Report

Network Monitor Report

Traffic Map Report

Use the Automated Correlation Engine

Automated Correlation Engine Concepts

Correlation Object

Correlated Events

View the Correlated Objects

Interpret Correlated Events

Use the Compromised Hosts Widget in the ACC

Take Packet Captures

Types of Packet Captures

Disable Hardware Offload

Take a Custom Packet Capture

Take a Threat Packet Capture

Take an Application Packet Capture

Take a Packet Capture for Unknown Applications

Take a Custom Application Packet Capture

Take a Packet Capture on the Management Interface

Monitor Applications and Threats

View and Manage Logs

Log Types and Severity Levels

Traffic Logs

Threat Logs

URL Filtering Logs

WildFire Submissions Logs

Data Filtering Logs

Correlation Logs

Tunnel Inspection Logs

Config Logs

System Logs

HIP Match Logs

GlobalProtect Logs

IP-Tag Logs

User-ID Logs

Alarms Logs

Authentication Logs

Unified Logs

View Logs

Filter Logs

Export Logs

Configure Log Storage Quotas and Expiration Periods

Schedule Log Exports to an SCP or FTP Server

Monitor Block List

View and Manage Reports

Report Types

View Reports

Configure the Expiration Period and Run Time for Reports

Disable Predefined Reports

Custom Reports

Generate Custom Reports

Generate Botnet Reports

Configure a Botnet Report

Interpret Botnet Report Output

Generate the SaaS Application Usage Report

Manage PDF Summary Reports

Generate User/Group Activity Reports

Manage Report Groups

Schedule Reports for Email Delivery

Manage Report Storage Capacity

View Policy Rule Usage

Use External Services for Monitoring

Configure Log Forwarding

Configure Email Alerts

Use Syslog for Monitoring

Configure Syslog Monitoring

Syslog Field Descriptions

Traffic Log Fields

Threat Log Fields

URL Filtering Log Fields

Data Filtering Log Fields

HIP Match Log Fields

GlobalProtect Log Fields

GlobalProtect Log Fields for PAN-OS 9.1.0 Through 9.1.2

GlobalProtect Log Fields for PAN-OS 9.1.3 and Later Releases

IP-Tag Log Fields

User-ID Log Fields

Tunnel Inspection Log Fields

SCTP Log Fields

Authentication Log Fields

Config Log Fields

System Log Fields

Correlated Events Log Fields

GTP Log Fields

Syslog Severity

Custom Log/Event Format

Escape Sequences

SNMP Monitoring and Traps

SNMP Support

Use an SNMP Manager to Explore MIBs and Objects

Identify a MIB Containing a Known OID

Walk a MIB

Identify the OID for a System Statistic or Trap

Enable SNMP Services for Firewall-Secured Network Elements

Monitor Statistics Using SNMP

Forward Traps to an SNMP Manager

Supported MIBs

MIB-II

IF-MIB

HOST-RESOURCES-MIB

ENTITY-MIB

ENTITY-SENSOR-MIB

ENTITY-STATE-MIB

IEEE 802.3 LAG MIB

LLDP-V2-MIB.my

BFD-STD-MIB

PAN-COMMON-MIB.my

PAN-GLOBAL-REG-MIB.my

PAN-GLOBAL-TC-MIB.my

PAN-LC-MIB.my

PAN-PRODUCT-MIB.my

PAN-ENTITY-EXT-MIB.my

PAN-TRAPS.my

Forward Logs to an HTTP/S Destination

NetFlow Monitoring

Configure NetFlow Exports

NetFlow Templates

Firewall Interface Identifiers in SNMP Managers and NetFlow Collectors

User-ID

User-ID Overview

User-ID Concepts

Group Mapping

User Mapping

Server Monitoring

Port Mapping

XFF Headers

Username Header Insertion

Authentication Policy and Captive Portal

Syslog

GlobalProtect

XML API

Client Probing

Enable User-ID

Map Users to Groups

Map IP Addresses to Users

Create a Dedicated Service Account for the User-ID Agent

Configure User Mapping Using the Windows User-ID Agent

Install the Windows-Based User-ID Agent

Configure the Windows User-ID Agent for User Mapping

Configure User Mapping Using the PAN-OS Integrated User-ID Agent

Configure Server Monitoring Using WinRM

Configure User-ID to Monitor Syslog Senders for User Mapping

Configure the PAN-OS Integrated User-ID Agent as a Syslog Listener

Configure the Windows User-ID Agent as a Syslog Listener

Map IP Addresses to Usernames Using Captive Portal

Captive Portal Authentication Methods

Captive Portal Modes

Configure Captive Portal

Configure User Mapping for Terminal Server Users

Configure the Palo Alto Networks Terminal Server (TS) Agent for User Mapping

Retrieve User Mappings from a Terminal Server Using the PAN-OS XML API

Send User Mappings to User-ID Using the XML API

Enable User- and Group-Based Policy

Enable Policy for Users with Multiple Accounts

Verify the User-ID Configuration

Deploy User-ID in a Large-Scale Network

Deploy User-ID for Numerous Mapping Information Sources

Windows Log Forwarding and Global Catalog Servers

Plan a Large-Scale User-ID Deployment

Configure Windows Log Forwarding

Configure User-ID for Numerous Mapping Information Sources

Insert Username in HTTP Headers

Redistribute User Mappings and Authentication Timestamps

Firewall Deployment for User-ID Redistribution

Configure User-ID Redistribution

Share User-ID Mappings Across Virtual Systems

App-ID

App-ID Overview

App-ID and HTTP/2 Inspection

Manage Custom or Unknown Applications

Manage New and Modified App-IDs

Apply Tags to an Application Filter

Create Custom Application Tags

Workflow to Best Incorporate New and Modified App-IDs

See the New and Modified App-IDs in a Content Release

See How New and Modified App-IDs Impact Your Security Policy

Ensure Critical New App-IDs are Allowed

Monitor New App-IDs

Disable and Enable App-IDs

Use Application Objects in Policy

Create an Application Group

Create an Application Filter

Create a Custom Application

Resolve Application Dependencies

Safely Enable Applications on Default Ports

Applications with Implicit Support

Security Policy Rule Optimization

Policy Optimizer Concepts

Sorting and Filtering Security Policy Rules

Clear Application Usage Data

Migrate Port-Based to App-ID Based Security Policy Rules

Rule Cloning Migration Use Case: Web Browsing and SSL Traffic

Add Applications to an Existing Rule

Identify Security Policy Rules with Unused Applications

High Availability for Application Usage Statistics

How to Disable Policy Optimizer

Application Level Gateways

Disable the SIP Application-level Gateway (ALG)

Use HTTP Headers to Manage SaaS Application Access

Understand SaaS Custom Headers

Domains used by the Predefined SaaS Application Types

Create HTTP Header Insertion Entries using Predefined Types

Create Custom HTTP Header Insertion Entries

Maintain Custom Timeouts for Data Center Applications

Threat Prevention

Best Practices for Securing Your Network from Layer 4 and Layer 7 Evasions

Set Up Antivirus, Anti-Spyware, and Vulnerability Protection

DNS Security

About DNS Security

Domain Generation Algorithm (DGA) Detection

DNS Tunneling Detection

Cloud-Delivered DNS Signatures and Protections

Enable DNS Security

Use DNS Queries to Identify Infected Hosts on the Network

How DNS Sinkholing Works

Configure DNS Sinkholing

Configure DNS Sinkholing for a List of Custom Domains

Configure the Sinkhole IP Address to a Local Server on Your Network

See Infected Hosts that Attempted to Connect to a Malicious Domain

Data Filtering

Create a Data Filtering Profile

Predefined Data Filtering Patterns

Set Up File Blocking

Prevent Brute Force Attacks

Customize the Action and Trigger Conditions for a Brute Force Signature

Enable Evasion Signatures

Prevent Credential Phishing

Methods to Check for Corporate Credential Submissions

Configure Credential Detection with the Windows User-ID Agent

Set Up Credential Phishing Prevention

Monitor Blocked IP Addresses

Threat Signature Categories

Create Threat Exceptions

Custom Signatures

Monitor and Get Threat Reports

Monitor Activity and Create Custom Reports Based on Threat Categories

Learn More About Threat Signatures

AutoFocus Threat Intelligence for Network Traffic

AutoFocus Intelligence Summary

Enable AutoFocus Threat Intelligence

View and Act on AutoFocus Intelligence Summary Data

Share Threat Intelligence with Palo Alto Networks

What Telemetry Data Does the Firewall Collect?

Passive DNS Monitoring

Enable Telemetry

Threat Prevention Resources

Decryption

Decryption Overview

Decryption Concepts

Keys and Certificates for Decryption Policies

SSL Forward Proxy

SSL Forward Proxy Decryption Profile

SSL Inbound Inspection

SSL Inbound Inspection Decryption Profile

SSL Protocol Settings Decryption Profile

SSH Proxy

SSH Proxy Decryption Profile

Decryption Profile for No Decryption

SSL Decryption for Elliptical Curve Cryptography (ECC) Certificates

Perfect Forward Secrecy (PFS) Support for SSL Decryption

SSL Decryption and Subject Alternative Names (SANs)

High Availability Support for Decrypted Sessions

Decryption Mirroring

Prepare to Deploy Decryption

Work with Stakeholders to Develop a Decryption Deployment Strategy

Develop a PKI Rollout Plan

Size the Decryption Firewall Deployment

Plan a Staged, Prioritized Deployment

Define Traffic to Decrypt

Create a Decryption Profile

Create a Decryption Policy Rule

Configure SSL Forward Proxy

Configure SSL Inbound Inspection

Configure SSH Proxy

Configure Server Certificate Verification for Undecrypted Traffic

Decryption Exclusions

Palo Alto Networks Predefined Decryption Exclusions

Exclude a Server from Decryption for Technical Reasons

Create a Policy-Based Decryption Exclusion

Enable Users to Opt Out of SSL Decryption

Temporarily Disable SSL Decryption

Configure Decryption Port Mirroring

Verify Decryption

Decryption Broker

How Decryption Broker Works

Decryption Broker Concepts

Decryption Broker: Forwarding Interfaces

Decryption Broker: Layer 3 Security Chain

Decryption Broker: Transparent Bridge Security Chain

Decryption Broker: Security Chain Session Flow

Decryption Broker: Multiple Security Chains

Decryption Broker: Security Chain Health Checks

Layer 3 Security Chain Guidelines

Configure Decryption Broker with One or More Layer 3 Security Chain

Transparent Bridge Security Chain Guidelines

Configure Decryption Broker with a Single Transparent Bridge Security Chain

Configure Decryption Broker with Multiple Transparent Bridge Security Chains

Activate Free Licenses for Decryption Features

URL Filtering

About Palo Alto Networks URL Filtering Solution

How Advanced URL Filtering Works

URL Filtering Use Cases

URL Categories

Security-Focused URL Categories

Malicious URL Categories

Verified URL Categories

Policy Actions You Can Take Based on URL Categories

Plan Your URL Filtering Deployment

URL Filtering Best Practices

Activate The Advanced URL Filtering Subscription

Configure URL Filtering

Test URL Filtering Configuration

Monitor Web Activity

Monitor Web Activity of Network Users

View the User Activity Report

Configure Custom URL Filtering Reports

Log Only the Page a User Visits

Create a Custom URL Category

URL Category Exceptions

Use an External Dynamic List in a URL Filtering Profile

Allow Password Access to Certain Sites

Safe Search Enforcement

Safe Search Settings for Search Providers

Block Search Results When Strict Safe Search Is Not Enabled

Transparently Enable Safe Search for Users

URL Filtering Response Pages

Customize the URL Filtering Response Pages

HTTP Header Logging

Request to Change the Category for a URL

Troubleshoot URL Filtering

Problems Activating Advanced URL Filtering

PAN-DB Cloud Connectivity Issues

URLs Classified as Not-Resolved

Incorrect Categorization

PAN-DB Private Cloud

M-600 Appliance for PAN-DB Private Cloud

Set Up the PAN-DB Private Cloud

Configure the PAN-DB Private Cloud

Configure the Firewalls to Access the PAN-DB Private Cloud

Configure Authentication with Custom Certificates on the PAN-DB Private Cloud

Quality of Service

QoS Overview

QoS Concepts

QoS for Applications and Users

QoS Policy

QoS Profile

QoS Classes

QoS Priority Queuing

QoS Bandwidth Management

QoS Egress Interface

QoS for Clear Text and Tunneled Traffic

Configure QoS

Configure QoS for a Virtual System

Enforce QoS Based on DSCP Classification

QoS Use Cases

Use Case: QoS for a Single User

Use Case: QoS for Voice and Video Applications

VPNs

VPN Deployments

Site-to-Site VPN Overview

Site-to-Site VPN Concepts

IKE Gateway

Tunnel Interface

Tunnel Monitoring

Internet Key Exchange (IKE) for VPN

IKE Phase 1

IKE Phase 2

Methods of Securing IPSec VPN Tunnels (IKE Phase 2)

IKEv2

Liveness Check

Cookie Activation Threshold and Strict Cookie Validation

Traffic Selectors

Hash and URL Certificate Exchange

SA Key Lifetime and Re-Authentication Interval

Set Up Site-to-Site VPN

Set Up an IKE Gateway

Export a Certificate for a Peer to Access Using Hash and URL

Import a Certificate for IKEv2 Gateway Authentication

Change the Key Lifetime or Authentication Interval for IKEv2

Change the Cookie Activation Threshold for IKEv2

Configure IKEv2 Traffic Selectors

Define Cryptographic Profiles

Define IKE Crypto Profiles

Define IPSec Crypto Profiles

Set Up an IPSec Tunnel

Set Up Tunnel Monitoring

Define a Tunnel Monitoring Profile

View the Status of the Tunnels