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ping mpls segment routing isis



Check the operability of MPLS segment routing label-switched path (LSP) connections added by ISIS protocol. Type Ctrl+c to interrupt a ping mpls segment routing isis command.


algorithm algorithm-id (Optional) Specify the flexible algorithm identifier. The range of values is 0 through 255. The default value is 0 which means no algorithm is configured. The algorithm-id in conjunction with the prefix is used to distinguish labelled SR paths.
count count

(Optional) Number of ping requests to send. If count is not specified, five ping requests are sent. The range of values is 1 through 1,000,000. The default value is 5.

destination address

(Optional) Specify an address other than the default ( for the ping echo requests. The address can be anything within the 127/8 subnet.


(Optional) Display detailed information about the echo requests sent and received.

exp forwarding-class

(Optional) Value of the forwarding class for the MPLS ping packets.


Ping an LDP-signaled LSP using the forwarding equivalence class (FEC) prefix and length.

instance routing-instance-name

(Optional) Allows you to ping a combination of the routing instance and forwarding equivalence class (FEC) associated with an LSP.

logical-system (all | logical-system-name)

(Optional) Perform this operation on all logical systems or on the specified logical system.

p2mp root-addr ip-address lsp-id identifier

(Optional) Ping the end points of a point-to-multipoint LSP. Enter the IP address of the point-to-multipoint LSP root and the ID number of the point-to-multipoint LSP.

size bytes

(Optional) Size of the LSP ping request packet (88 through 65468 bytes). Packets are 4-byte aligned. For example, If you enter a size of 89, 90, 91, or 92, the router or switch uses a size value of 92 bytes. If you enter a packet size that is smaller than the minimum size, an error message is displayed reminding you of the 88-byte minimum.

source source-address

(Optional) IP address of the outgoing interface. This address is sent in the IP source address field of the ping request. If this option is not specified, the default address is usually the loopback interface (lo.0).


(Optional) Protocol stitched on intermediate node.


(Optional) Automatically determine the size of the maximum transmission unit (MTU).

Required Privilege Level


Output Fields

When you enter this command, you are provided feedback on the status of your request. An exclamation point (!) indicates that an echo reply was received. A period (.) indicates that an echo reply was not received within the timeout period. An x indicates that an echo reply was received with an error code. Packets with error codes are not counted in the received packets count. They are accounted for separately.

Sample Output

ping mpls segment-routing isis

ping mpls segment-routing isis

ping mpls segment-routing isis (Labelled IS-IS flexible-algorithm IPv4 ping)

ping mpls segment-routing isis (Labelled IS-IS flexible-algorithm IPv6 ping)

Release Information

Command introduced in Junos OS Release 19.1R1

algorithm option introduced in Junos OS Release 23.1R1 and Junos OS Evolved Release 23.1R1.