>
    Tunnel Inspection Log Fields
    Focus
    Download PDF
    Focus
    1. Home
    2. PAN-OS
    3. Monitoring
    4. Use Syslog for Monitoring
    5. Syslog Field Descriptions
    6. Tunnel Inspection Log Fields
    Download PDF

    Tunnel Inspection Log Fields

    Table of Contents
    End-of-Life (EoL)

    Tunnel Inspection Log Fields

    Format: FUTURE_USE, Receive Time, Serial Number, Type, Subtype, FUTURE_USE, Generated Time, Source Address, Destination Address, NAT Source IP, NAT Destination IP, Rule Name, Source User, Destination User, Application, Virtual System, Source Zone, Destination Zone, Inbound Interface, Outbound Interface, Log Action, FUTURE_USE, Session ID, Repeat Count, Source Port, Destination Port, NAT Source Port, NAT Destination Port, Flags, Protocol, Action, Severity, Sequence Number, Action Flags, Source Location, Destination Location, Device Group Hierarchy Level 1, Device Group Hierarchy Level 2, Device Group Hierarchy Level 3, Device Group Hierarchy Level 4, Virtual System Name, Device Name, Tunnel ID/IMSI, Monitor Tag/IMEI, Parent Session ID, Parent Start Time, Tunnel, Bytes, Bytes Sent, Bytes Received, Packets, Packets Sent, Packets Received, Maximum Encapsulation, Unknown Protocol, Strict Check, Tunnel Fragment, Sessions Created, Sessions Closed, Session End Reason, Action Source, Start Time, Elapsed Time, Tunnel Inspection Rule, Remote User IP, Remote User ID, Rule UUID, PCAP ID, Dynamic User Group, Source External Dynamic List, Destination External Dynamic List, High Resolution Timestamp, A Slice Differentiator, A Slice Service Type, PDU Session ID, Application Subcategory, Application Category, Application Technology, Application Risk, Application Characteristic, Application Container, Application SaaS, Application Sanctioned State, Cluster Name
    Field Name
    Description
    Receive Time (receive_time or cef-formatted-receive_time)
    Month, day, and time the log was received at the management plane.
    Serial Number (serial)
    Serial number of the firewall that generated the log.
    Type (type)
    Type of log as it pertains to the session: START or END.
    Threat/Content Type (subtype)
    Subtype of traffic log; values are start, end, drop, and deny
    • Start—session started
    • End—session ended
    • Drop—session dropped before the application is identified and there is no rule that allows the session.
    • Deny—session dropped after the application is identified and there is a rule to block or no rule that allows the session.
    Generated Time (time_generated or cef-formatted-time_generated)
    Time the log was generated on the dataplane.
    Source Address (src)
    Source IP address of packets in the session.
    Destination Address (dst)
    Destination IP address of packets in the session.
    NAT Source IP (natsrc)
    If Source NAT performed, the post-NAT Source IP address.
    NAT Destination IP (natdst)
    If Destination NAT performed, the post-NAT Destination IP address.
    Rule Name (rule)
    Name of the Security policy rule in effect on the session.
    Source User (srcuser)
    Source User ID of packets in the session.
    Destination User (dstuser)
    Destination User ID of packets in the session.
    Application (app)
    Tunneling protocol used in the session.
    Virtual System (vsys)
    Virtual System associated with the session.
    Source Zone (from)
    Source zone of packets in the session.
    Destination Zone (to)
    Destination zone of packets in the session.
    Inbound Interface (inbound_if)
    Interface that the session was sourced from.
    Outbound Interface (outbound_if)
    Interface that the session was destined to.
    Log Action (logset)
    Log Forwarding Profile that was applied to the session.
    Session ID (sessionid)
    Session ID of the session being logged.
    Repeat Count (repeatcnt)
    Number of sessions with same Source IP, Destination IP, Application, and Subtype seen within 5 seconds.
    Source Port (sport)
    Source port utilized by the session.
    Destination Port (dport)
    Destination port utilized by the session.
    NAT Source Port (natsport)
    Post-NAT source port.
    NAT Destination Port (natdport)
    Post-NAT destination port.
    Flags (flags)
    32-bit field that provides details on session; this field can be decoded by AND-ing the values with the logged value:
    • 0x80000000 —session has a packet capture (PCAP)
    • 0x02000000 —IPv6 session
    • 0x01000000 —SSL session was decrypted (SSL Proxy)
    • 0x00800000 —session was denied via URL filtering
    • 0x00400000 —session has a NAT translation performed (NAT)
    • 0x00200000 —user information for the session was captured through Authentication Portal
    • 0x00080000 —X-Forwarded-For value from a proxy is in the source user field
    • 0x00040000 —log corresponds to a transaction within a http proxy session (Proxy Transaction)
    • 0x00008000 —session is a container page access (Container Page)
    • 0x00002000 —session has a temporary match on a rule for implicit application dependency handling. Available in PAN-OS 5.0.0 and above.
    • 0x00000800 —symmetric return was used to forward traffic for this session
    IP Protocol (proto)
    IP protocol associated with the session.
    Action (action)
    Action taken for the session; possible values are:
    • Allow—session was allowed by policy
    • Deny—session was denied by policy
    • Drop—session was dropped silently
    • Drop ICMP—session was silently dropped with an ICMP unreachable message to the host or application
    • Reset both—session was terminated and a TCP reset is sent to both the sides of the connection
    • Reset client—session was terminated and a TCP reset is sent to the client
    • Reset server—session was terminated and a TCP reset is sent to the server
    Severity (severity)
    Severity associated with the event; values are informational, low, medium, high, critical.
    Sequence Number (seqno)
    A 64-bit log entry identifier incremented sequentially; each log type has a unique number space. This field is not supported on PA-7000 Series firewalls.
    Action Flags (actionflags)
    A bit field indicating if the log was forwarded to Panorama.
    Source Location (srcloc)
    Source country or Internal region for private addresses; maximum length is 32 bytes.
    Destination Location (dstloc)
    Destination country or Internal region for private addresses. Maximum length is 32 bytes.
    Device Group Hierarchy (dg_hier_level_1 to dg_hier_level_4)
    A sequence of identification numbers that indicate the device group’s location within a device group hierarchy. The firewall (or virtual system) generating the log includes the identification number of each ancestor in its device group hierarchy. The shared device group (level 0) is not included in this structure.
    If the log values are 12, 34, 45, 0, it means that the log was generated by a firewall (or virtual system) that belongs to device group 45, and its ancestors are 34, and 12. To view the device group names that correspond to the value 12, 34 or 45, use one of the following methods:
    API query: 
    /api/?type=op&cmd=<show><dg-hierarchy></dg-hierarchy></show>
    Virtual System Name (vsys_name)
    The name of the virtual system associated with the session; only valid on firewalls enabled for multiple virtual systems.
    Device Name (device_name)
    The hostname of the firewall on which the session was logged.
    Tunnel ID (tunnelid)
    ID of the tunnel being inspected or the International Mobile Subscriber Identity (IMSI) ID of the mobile user.
    Monitor Tag (monitortag)
    Monitor name you configured for the Tunnel Inspection policy rule or the International Mobile Equipment Identity (IMEI) ID of the mobile device.
    Parent Session ID (parent_session_id)
    ID of the session in which this session is tunneled. Applies to inner tunnel (if two levels of tunneling) or inside content (if one level of tunneling) only.
    Parent Start Time (parent_start_time)
    Year/month/day hours:minutes:seconds that the parent tunnel session began.
    Tunnel Type (tunnel)
    Type of tunnel, such as GRE or IPSec.
    Bytes (bytes)
    Number of bytes in the session.
    Bytes Sent (bytes_sent)
    Number of bytes in the client-to-server direction of the session.
    Bytes Received (bytes_received)
    Number of bytes in the server-to-client direction of the session.
    Packets (packets)
    Number of total packets (transmit and receive) for the session.
    Packets Sent (pkts_sent)
    Number of client-to-server packets for the session.
    Packets Received (pkts_received)
    Number of server-to-client packets for the session.
    Maximum Encapsulation (max_encap)
    Number of packets the firewall dropped because the packet exceeded the maximum number of encapsulation levels configured in the Tunnel Inspection policy rule (Drop packet if over maximum tunnel inspection level).
    Unknown Protocol (unknown_proto)
    Number of packets the firewall dropped because the packet contains an unknown protocol, as enabled in the Tunnel Inspection policy rule (Drop packet if unknown protocol inside tunnel).
    Strict Checking (strict_check)
    Number of packets the firewall dropped because the tunnel protocol header in the packet failed to comply with the RFC for the tunnel protocol, as enabled in the Tunnel Inspection policy rule (Drop packet if tunnel protocol fails strict header check).
    Tunnel Fragment (tunnel_fragment)
    Number of packets the firewall dropped because of fragmentation errors.
    Sessions Created (sessions_created)
    Number of inner sessions created.
    Sessions Closed (sessions_closed)
    Number of completed/closed sessions created.
    Session End Reason (session_end_reason)
    The reason a session terminated. If the termination had multiple causes, this field displays only the highest priority reason. The possible session end reason values are as follows, in order of priority (where the first is highest):
    • threat—The firewall detected a threat associated with a reset, drop, or block (IP address) action.
    • policy-deny—The session matched a security rule with a deny or drop action.
    • decrypt-cert-validation—The session terminated because you configured the firewall to block SSL forward proxy decryption or SSL inbound inspection when the session uses client authentication or when the session uses a server certificate with any of the following conditions: expired, untrusted issuer, unknown status, or status verification time-out. This session end reason also displays when the server certificate produces a fatal error alert of type bad_certificate, unsupported_certificate, certificate_revoked, access_denied, or no_certificate_RESERVED (SSLv3 only).
    • decrypt-unsupport-param—The session terminated because you configured the firewall to block SSL forward proxy decryption or SSL inbound inspection when the session uses an unsupported protocol version, cipher, or SSH algorithm. This session end reason is displays when the session produces a fatal error alert of type unsupported_extension, unexpected_message, or handshake_failure.
    • decrypt-error—The session terminated because you configured the firewall to block SSL forward proxy decryption or SSL inbound inspection when firewall resources or the hardware security module (HSM) were unavailable. This session end reason is also displayed when you configured the firewall to block SSL traffic that has SSH errors or that produced any fatal error alert other than those listed for the decrypt-cert-validation and decrypt-unsupport-param end reasons.
    • tcp-rst-from-client—The client sent a TCP reset to the server.
    • tcp-rst-from-server—The server sent a TCP reset to the client.
    • resources-unavailable—The session dropped because of a system resource limitation. For example, the session could have exceeded the number of out-of-order packets allowed per flow or the global out-of-order packet queue.
    • tcp-fin—One host or both hosts in the connection sent a TCP FIN message to close the session.
    • tcp-reuse—A session is reused and the firewall closes the previous session.
    • decoder—The decoder detects a new connection within the protocol (such as HTTP-Proxy) and ends the previous connection.
    • aged-out—The session aged out.
    • unknown—This value applies in the following situations:
      • Session terminations that the preceding reasons do not cover (for example, a clear session all command).
      • For logs generated in a PAN-OS release that does not support the session end reason field (releases older than PAN-OS 6.1), the value will be unknown after an upgrade to the current PAN-OS release or after the logs are loaded onto the firewall.
      • In Panorama, logs received from firewalls for which the PAN-OS version does not support session end reasons will have a value of unknown.
    • n/a—This value applies when the traffic log type is not end.
    Action Source (action_source)
    Specifies whether the action taken to allow or block an application was defined in the application or in policy. The actions can be allow, deny, drop, reset- server, reset-client or reset-both for the session.
    Start Time (start)
    Year/month/day hours:minutes:seconds that the session began.
    Elapsed Time (elapsed)
    Elapsed time of the session.
    Tunnel Inspection Rule (tunnel_insp_rule)
    Name of the tunnel inspection rule matching the cleartext tunnel traffic.
    Remote User IP (remote_user_ip)
    IPv4 or IPv6 address of a remote user.
    Remote User ID (remote_user_id)
    IMSI identity of a remote user, and if available, one IMEI identity or one MSISDN identity.
    Security Rule UUID (rule_uuid)
    The UUID that permanently identifies the rule.
    PCAP ID (pcap_id)
    Unique packet capture ID that defines the location of the pcap file on the firewall.
    Dynamic User Group Name (dynusergroup_name)
    The name of the dynamic user group that contains the user who initiated the session.
    Source External Dynamic List (src_edl)
    The name of the external dynamic list that contains the source IP address of the traffic.
    Destination External Dynamic List (dst_edl)
    The name of the external dynamic list that contains the destination IP address of the traffic.
    High Resolution Timestamp (high_res timestamp)
    Time in milliseconds the log was received at the management plane.
    The format for this new field is YYYY-MM-DDThh:ss:sssTZD:
    • YYYY—Four digit year
    • MM—Two-digit month
    • DD—Two-digit day of the month (01 through 31)
    • T—Indicator for the beginning of the timestamp
    • hh—Two-digit hour using 24-hour time (00 through 23)
    • mm—Two-digit minute (00 through 59)
    • ss—Two-digit second (00 through 60)
    • sss—One or more digits for millisecond
    • TZD—Time zone designator (+hh:mm or -hh:mm)
    The High Resolution Timestamp is supported for logs received from managed firewalls running PAN-OS 11.0 and later releases. Logs received from managed firewalls running PAN-OS 9.1 and earlier releases display a 1969-12-31T16:00:00:000-8:00 timestamp regardless of when the log was received.
    A Slice Differentiator (nssai_sd)
    The A Slice Differentiator of the Network Slice ID.
    A Slice Service Type (nssai_sd)
    The A Slice Service Type of the Network Slice ID.
    PDU Session ID (pdu_session_id)
    Session ID for the collection of L4 segments inside a tunnel.
    Application Subcategory (subcategory_of_app)
    The application subcategory specified in the application configuration properties.
    Application Category (category_of_app)
    The application category specified in the application configuration properties. Values are:
    • business-systems
    • collaboration
    • general-internet
    • media
    • networking
    • saas
    Application Technology (technology_of_app)
    The application technology specified in the application configuration properties. Values are:
    • browser-based
    • client-server
    • network-protocol
    • peer-to-peer
    Application Risk (risk_of_app)
    Risk level associated with the application (1=lowest to 5=highest).
    Application Characteristic (characteristic_of_app)
    Comma-separated list of applicable characteristic of the application
    Application Container (container_of_app)
    The parent application for an application.
    Application SaaS (is_saas_of_app)
    Displays 1 if a SaaS application or 0 if not a SaaS application.
    Application Sanctioned State (sanctioned_state_of_app)
    Displays 1 if application is sanctioned or 0 if application is not sanctioned.
    Cluster Name (cluster_name)
    Name of the CN-Series firewall cluster.

    © 2024 Palo Alto Networks, Inc. All rights reserved.