- play_arrow Overview
- play_arrow Operation, Administration, and Management Features
- play_arrow Ethernet OAM and Connectivity Fault Management for Routers
- Introduction to OAM Connectivity Fault Management (CFM)
- Configure Connectivity Fault Management (CFM)
- CFM Action Profile
- Ethernet Local Management Interface
- CFM Support for CCC Encapsulated Packets
- Configure Unified ISSU for 802.1ag CFM
- CFM Monitoring between CE and PE Devices
- Configure Continuity Check Messages
- Example: Configure Ethernet CFM on Physical Interfaces
- Example: Configure Ethernet CFM on Bridge Connections
- Example: Configure Ethernet CFM over VPLS
- play_arrow Link Fault Management for Routers
- play_arrow Ethernet OAM Link Fault Management for Switches
- play_arrow Ethernet OAM Connectivity Fault Management for Switches
- play_arrow Ethernet Frame Delay
- Ethernet Frame Delay Measurements on Switches
- Configure MEP Interfaces on Switches to Support Ethernet Frame Delay Measurements (CLI Procedure)
- Configure One-Way Ethernet Frame Delay Measurements on Switches (CLI Procedure)
- Configure an Iterator Profile on a Switch (CLI Procedure)
- Trigger an Ethernet Frame Delay Measurement Session on a Switch
- Configure Two-Way Ethernet Frame Delay Measurements on Switches (CLI Procedure)
- play_arrow Ethernet Service OAM (ITU-TY.1731) for Routers
- ITU-T Y.1731 Ethernet Service OAM Overview
- Configure Ethernet Frame Delay Measurement Sessions
- Configuring MEP Interfaces to Support Ethernet Frame Delay Measurements
- Configure Ethernet Frame Loss Measurement
- Configure an Iterator Profile
- Configure Ethernet Synthetic Loss Measurements
- Ethernet Alarm Indication
- Inline Transmission Mode
-
- play_arrow Network Monitoring by using SNMP
- SNMP Architecture and SNMP MIBs Overview
- Understand SNMP Implementation in Junos OS
- Configure SNMP in Junos OS
- Configure Options on Managed Devices for Better SNMP Response Time
- Enterprise Specific Utility MIB to Enhance SNMP Coverage
- Optimize the Network Management System Configuration for the Best Results
- Interfaces to Accept SNMP Requests
- Configure SNMP for Routing Instances
- Configure SNMP Remote Operations
- SNMP Traps
- SNMP Traps Supported by Junos OS
- Trace SNMP Activity
- Access Privileges for an SNMP Group
- Configure Local Engine ID on SNMPv3
- Configure SNMPv3
- Configure SNMPv3 Authentication Type and Encryption Type
- SNMPv3 Traps
- SNMPv3 Informs
- SNMP Communities
- MIB Views
- SNMP MIBs Supported by Junos OS and Junos OS Evolved
- Junos OS SNMP FAQs
- play_arrow Remote Network Monitoring (RMON) with SNMP Alarms and Events
- play_arrow Accounting Options
- play_arrow Monitoring Options
- play_arrow Interface Alarms
- play_arrow IP Monitoring
- play_arrow sFlow Monitoring Technology
- play_arrow Adaptive Sampling for Routers and Switches
- play_arrow Packet Flow Accelerator Diagnostics Software
-
- play_arrow Monitoring Common Security Features
- play_arrow Performance Management
- play_arrow Port Mirroring
- play_arrow Port Mirroring and Analyzers
- Port Mirroring and Analyzers
- Configuring Port Mirroring and Analyzers
- Configuring Port Mirroring Instances
- Configuring Port Mirroring on Physical Interfaces
- Configuring Port Mirroring on Logical Interfaces
- Configuring Port Mirroring for Multiple Destinations
- Configuring Port Mirroring for Remote Destinations
- Configuring Port Mirroring Local and Remote Analysis
- 1:N Port Mirroring to Multiple Destinations on Switches
- Example: Configure Port Mirroring with Family any and a Firewall Filter
- Monitoring Port Mirroring
- Configure Packet Mirroring with Layer 2 Headers for Layer 3 Forwarded Traffic
- Troubleshooting Port Mirroring
-
- play_arrow System Log Messages
- play_arrow Configuration Statements and Operational Commands
Using MPLS to Diagnose LSPs, VPNs, and Layer 2 Circuits
MPLS Connection Checking Overview
Use either the J-Web ping MPLS diagnostic tool or the CLI commands ping
mpls
, ping mpls l2circuit
, ping mpls
l2vpn
, and ping mpls l3vpn
to diagnose the state of
label-switched paths (LSPs), Layer 2 and Layer 3 virtual private networks (VPNs), and
Layer 2 circuits.
Based on how the LSP or VPN outbound (egress) node at the remote endpoint of the connection replies to the probes, you can determine the connectivity of the LSP or VPN.
Each probe is an echo request sent to the LSP or VPN exit point as an MPLS packet with a UDP payload. If the outbound node receives the echo request, it checks the contents of the probe and returns a value in the UDP payload of the response packet. If the device receives the response packet, it reports a successful ping response.
Responses that take longer than 2 seconds are identified as failed probes.
Table 1
summarizes the options for using either the J-Web ping MPLS diagnostic tool or the CLI
ping mpls
command to display information about MPLS connections in
VPNs and LSPs.
J-Web Ping MPLS Tool | ping mpls Command | Purpose | Additional Information |
---|---|---|---|
Ping RSVP-signaled LSP |
| Checks the operability of an LSP that has been set up by the Resource Reservation Protocol (RSVP). The device pings a particular LSP using the configured LSP name. | When an RSVP-signaled LSP has several paths, the device sends the ping requests on the path that is currently active. |
Ping LDP-signaled LSP |
| Checks the operability of an LSP that has been set up by the Label Distribution Protocol (LDP). The device pings a particular LSP using the forwarding equivalence class (FEC) prefix and length. | When an LDP-signaled LSP has several gateways, the device sends the ping requests through the first gateway. Ping requests sent to LDP-signaled LSPs use only the master routing instance. |
Ping LSP to Layer 3 VPN prefix |
| Checks the operability of the connections related to a Layer 3 VPN. The device tests whether a prefix is present in a provider edge (PE) device’s VPN routing and forwarding (VRF) table, by means of a Layer 3 VPN destination prefix. | The device does not test the connection between a PE device and a customer edge (CE) router. |
Locate LSP using interface name |
| Checks the operability of the connections related to a Layer 2 VPN. The device directs outgoing request probes out the specified interface. | – |
Instance to which this connection belongs |
| Checks the operability of the connections related to a Layer 2 VPN. The device pings on a combination of the Layer 2 VPN routing instance name, the local site identifier, and the remote site identifier, to test the integrity of the Layer 2 VPN circuit (specified by the identifiers) between the inbound and outbound PE routers. | – |
Locate LSP from interface name |
| Checks the operability of the Layer 2 circuit connections. The device directs outgoing request probes out the specified interface. | – |
Locate LSP from virtual circuit information |
| Checks the operability of the Layer 2 circuit connections. The device pings on a combination of the IPv4 prefix and the virtual circuit identifier on the outbound PE router, testing the integrity of the Layer 2 circuit between the inbound and outbound PE routers. | – |
Ping end point of LSP |
| Checks the operability of an LSP endpoint. The device pings an LSP endpoint using either an LDP FEC prefix or an RSVP LSP endpoint address. | – |
Before using the ping MPLS feature, make sure that the receiving interface on the VPN or
LSP remote endpoint has MPLS enabled, and that the loopback interface on the outbound
node is configured as 127.0.0.1
. The source address for MPLS probes
must be a valid address on the J Series device.
This section includes the following topics:
MPLS Enabled
To process ping MPLS requests, the remote endpoint of the VPN or LSP must be configured appropriately. You must enable MPLS on the receiving interface of the outbound node for the VPN or LSP. If MPLS is not enabled, the remote endpoint drops the incoming request packets and returns an “ICMP host unreachable” message to the J Series device.
Loopback Address
The loopback address (lo0
) on the outbound node must be configured
as 127.0.0.1
. If this interface address is not configured
correctly, the outbound node does not have this forwarding entry. It drops the
incoming request packets and returns a “host unreachable” message to the J Series
device.
Source Address for Probes
The source IP address you specify for a set of probes must be an address configured on one of the J Series device interfaces. If it is not a valid J Series device address, the ping request fails with the error message “Can't assign requested address.”
Using the ping Command
You can perform certain tasks only through the CLI. Use the CLI ping
command to verify that a host can be reached over the network. This command is
useful for diagnosing host and network connectivity problems. The device sends a
series of ICMP echo (ping) requests to a specified host and receives ICMP echo
responses.