This article describes the issue of slow response to any interactive commands being entered in the router or when the configuration is committed with accounting/ TAC+ configured.
Slow response to any interactive commands being entered in the router or when the configuration is committed with accounting/ TAC+ configured.
Scenario : If the accounting/ TAC+ server is configured and the route is there in the routing table, but the server is not operational, then the router waits for the configured timeout to expire; before executing the command.
Configuration :
accounting { events [ change-log interactive-commands ]; destination { tacplus { server { 192.168.1.1 { secret "$ABC123"; ## SECRET-DATA timeout 10;---> timeout configured is 10 ms } } } } }
Route entry for the server:
User@router> show route table inet.0 192.168.1.1 inet.0: 6 destinations, 6 routes (6 active, 0 holddown, 0 hidden) + = Active Route, - = Last Active, * = Both 192.168.1.1/32 *[Static/5] 00:13:22 > to 10.0.75.254 via fxp0.0
The show interfaces terse interactive command is issued during the Jun 15 03:59:20 timestamp:
Jun 15 03:59:20 Router mgd[1325]: UI_CMDLINE_READ_LINE: User 'lab', command 'show interfaces terse ' Packets initiated towards the server 192.168.1.1 -----original packet----- 00:00:00:00:3e:ff > 00:00:00:00:21:d0, ethertype IPv4 (0x0800), length 78: (tos 0x0, ttl 64, id 24838, offset 0, flags [DF], proto: TCP (6), length: 64) 10.0.75.157.59638 > 192.168.1.1.49: S 3428893759:3428893759(0) win 65535 <mss 1460,nop,wscale 1,nop,nop,timestamp 4268529 0,sackOK,eol> 03:59:20.651409 In Juniper PCAP Flags [Ext, In], PCAP Extension(s) total length 16 Device Media Type Extension TLV #3, length 1, value: Ethernet (1) Logical Interface Encapsulation Extension TLV #6, length 1, value: Ethernet (14) Device Interface Index Extension TLV #1, length 2, value: 16384 Logical Interface Index Extension TLV #4, length 4, value: 4 -----original packet--- 00:00:00:00:3e:ff > 00:00:00:00:21:d0, ethertype IPv4 (0x0800), length 78: (tos 0x0, ttl 64, id 24927, offset 0, flags [DF], proto: TCP (6), length: 64) 10.0.75.157.59638 > 192.168.1.1.49: S 3428893759:3428893759(0) win 65535 <mss 1460,nop,wscale 1,nop,nop,timestamp 4271529 0,sackOK,eol> 03:59:24.124410 Out Juniper PCAP Flags [Ext], PCAP Extension(s) total length 16 Device Media Type Extension TLV #3, length 1, value: Ethernet (1) Logical Interface Encapsulation Extension TLV #6, length 1, value: Ethernet (14) Device Interface Index Extension TLV #1, length 2, value: 16384 Logical Interface Index Extension TLV #4, length 4, value: 4 -----original packet----- 00:00:00:00:3e:ff > 00:00:00:00:21:d0, ethertype IPv4 (0x0800), length 78: (tos 0x0, ttl 64, id 25005, offset 0, flags [DF], proto: TCP (6), length: 64) 10.0.75.157.59638 > 192.168.1.1.49: S 3428893759:3428893759(0) win 65535 <mss 1460,nop,wscale 1,nop,nop,timestamp 4274729 0,sackOK,eol> 03:59:26.621784 In Juniper PCAP Flags [Ext, In], PCAP Extension(s) total length 16 Device Media Type Extension TLV #3, length 1, value: Ethernet (1) Logical Interface Encapsulation Extension TLV #6, length 1, value: Ethernet (14) Device Interface Index Extension TLV #1, length 2, value: 16384 Logical Interface Index Extension TLV #4, length 4, value: 4 -----original packet----- 00:00:00:00:3e:ff > 00:00:00:00:21:d0, ethertype IPv4 (0x0800), length 62: (tos 0x0, ttl 64, id 25083, offset 0, flags [DF], proto: TCP (6), length: 48) 10.0.75.157.59638 > 192.168.1.1.49: S 3428893759:3428893759(0) win 65535 <mss 1460,sackOK,eol> 03:59:30.237342 Out Juniper PCAP Flags [Ext], PCAP Extension(s) total length 16 Device Media Type Extension TLV #3, length 1, value: Ethernet (1) Logical Interface Encapsulation Extension TLV #6, length 1, value: Ethernet (14) Device Interface Index Extension TLV #1, length 2, value: 16384 Logical Interface Index Extension TLV #4, length 4, value: 4 -----original packet-----
Jun 15 03:59:20 Router mgd[1325]: UI_CMDLINE_READ_LINE: User 'lab', command 'show interfaces terse ' Packets initiated towards the server 192.168.1.1
-----original packet----- 00:00:00:00:3e:ff > 00:00:00:00:21:d0, ethertype IPv4 (0x0800), length 78: (tos 0x0, ttl 64, id 24838, offset 0, flags [DF], proto: TCP (6), length: 64) 10.0.75.157.59638 > 192.168.1.1.49: S 3428893759:3428893759(0) win 65535 <mss 1460,nop,wscale 1,nop,nop,timestamp 4268529 0,sackOK,eol> 03:59:20.651409 In Juniper PCAP Flags [Ext, In], PCAP Extension(s) total length 16 Device Media Type Extension TLV #3, length 1, value: Ethernet (1) Logical Interface Encapsulation Extension TLV #6, length 1, value: Ethernet (14) Device Interface Index Extension TLV #1, length 2, value: 16384 Logical Interface Index Extension TLV #4, length 4, value: 4 -----original packet--- 00:00:00:00:3e:ff > 00:00:00:00:21:d0, ethertype IPv4 (0x0800), length 78: (tos 0x0, ttl 64, id 24927, offset 0, flags [DF], proto: TCP (6), length: 64) 10.0.75.157.59638 > 192.168.1.1.49: S 3428893759:3428893759(0) win 65535 <mss 1460,nop,wscale 1,nop,nop,timestamp 4271529 0,sackOK,eol>
03:59:24.124410 Out Juniper PCAP Flags [Ext], PCAP Extension(s) total length 16 Device Media Type Extension TLV #3, length 1, value: Ethernet (1) Logical Interface Encapsulation Extension TLV #6, length 1, value: Ethernet (14) Device Interface Index Extension TLV #1, length 2, value: 16384 Logical Interface Index Extension TLV #4, length 4, value: 4 -----original packet----- 00:00:00:00:3e:ff > 00:00:00:00:21:d0, ethertype IPv4 (0x0800), length 78: (tos 0x0, ttl 64, id 25005, offset 0, flags [DF], proto: TCP (6), length: 64) 10.0.75.157.59638 > 192.168.1.1.49: S 3428893759:3428893759(0) win 65535 <mss 1460,nop,wscale 1,nop,nop,timestamp 4274729 0,sackOK,eol> 03:59:26.621784 In Juniper PCAP Flags [Ext, In], PCAP Extension(s) total length 16 Device Media Type Extension TLV #3, length 1, value: Ethernet (1) Logical Interface Encapsulation Extension TLV #6, length 1, value: Ethernet (14) Device Interface Index Extension TLV #1, length 2, value: 16384 Logical Interface Index Extension TLV #4, length 4, value: 4 -----original packet----- 00:00:00:00:3e:ff > 00:00:00:00:21:d0, ethertype IPv4 (0x0800), length 62: (tos 0x0, ttl 64, id 25083, offset 0, flags [DF], proto: TCP (6), length: 48) 10.0.75.157.59638 > 192.168.1.1.49: S 3428893759:3428893759(0) win 65535 <mss 1460,sackOK,eol> 03:59:30.237342 Out Juniper PCAP Flags [Ext], PCAP Extension(s) total length 16 Device Media Type Extension TLV #3, length 1, value: Ethernet (1) Logical Interface Encapsulation Extension TLV #6, length 1, value: Ethernet (14) Device Interface Index Extension TLV #1, length 2, value: 16384 Logical Interface Index Extension TLV #4, length 4, value: 4 -----original packet-----
The output is seen by the Jun 15 03:59:30 timestamp, after a delay of 10ms (when the timeout expires):
User@router> show interfaces terse Jun 15 03:59:30--------------------------> There is a delay of 10ms after issuing the command Interface Admin Link Proto Local Remote lc-0/0/0 up up lc-0/0/0.32769 up up vpls pfe-0/0/0 up up pfe-0/0/0.16383 up up inet inet6 pfh-0/0/0 up up pfh-0/0/0.16383 up up inet xe-0/0/0 up up xe-0/0/1 up up xe-0/0/2 up down xe-0/0/3 up up ge-1/0/0 up down
This is expected behavior of the router, when the accounting/ TAC+ server is configured and the entry for the same is available in the routing table. But when the server is not operational, the router waits for the reply from the server, until the configured timeout expires and it then executes the issued command.
2020-02-19: minor non-technical edits.