ELAM Packet capture:
Step 1: Kindly check the hardware module to see what inputs must be there in command i.e. tah/roc/app
/// N9K-C*-EX- Leaf ----------------------- tah
N9K-C*FX/FXP/FX2 -Leaf ------------ roc
N9K-C*-GX – Leaf ----------------------app//
Recommended Best Practices:
To capture a packet with VLAN encapsulation on a downlink port, use 'in-select 6'.
To capture a packet with VXLAN encapsulation (whether from a spine or a vleaf with VXLAN encapsulation), use 'in-select 14'.
L3 traffic
ELAM JI
=========================
Leaf1
=========================
debug platform internal tah elam asic 0
trigger reset
trigger init in-select 6 out-select 1
set outer ipv4 src_ip 192.168.11.11 dst_ip 192.168.12.12
start
status
ereport
Python available. Continue ELAM decode with LC Pkg
ELAM REPORT
======================================================================================================================================================
Trigger/Basic Information
======================================================================================================================================================
ELAM Report File : /tmp/logs/elam_2024-06-29-02m-18h-46s.txt
In-Select Trigger : Outerl2-outerl3-outerl4( 6 )
Out-Select Trigger : Pktrw-sideband-drpvec( 1 )
ELAM Captured Device : LEAF
Packet Direction : ingress
Triggered ASIC type : Homewood
Triggered ASIC instance : 0
Triggered Slice : 0
Incoming Interface : 0x58( 0x58 )
( Slice Source ID(Ss) in "show plat int hal l2 port gpd" )
======================================================================================================================================================
Captured Packet
======================================================================================================================================================
------------------------------------------------------------------------------------------------------------------------------------------------------
Outer Packet Attributes
------------------------------------------------------------------------------------------------------------------------------------------------------
Outer Packet Attributes : l2uc ipv4 ip ipuc ipv4uc
Opcode : OPCODE_UC
------------------------------------------------------------------------------------------------------------------------------------------------------
Outer L2 Header
------------------------------------------------------------------------------------------------------------------------------------------------------
Destination MAC : 0022.BDF8.19FF
Source MAC : ACF2.C5F8.2F81
802.1Q tag is valid : yes( 0x1 )
CoS : 0( 0x0 )
Access Encap VLAN : 3311( 0xCEF )
------------------------------------------------------------------------------------------------------------------------------------------------------
Outer L3 Header
------------------------------------------------------------------------------------------------------------------------------------------------------
L3 Type : IPv4
IP Version : 4
DSCP : 0
IP Packet Length : 84 ( = IP header(28 bytes) + IP payload )
Don't Fragment Bit : not set
TTL : 255
IP Protocol Number : ICMP
IP CheckSum : 13018( 0x32DA )
Destination IP : 192.168.12.12
Source IP : 192.168.11.11
module-1(DBG-elam-insel6)# show plat int hal l2 port gpd
For Incoming interface
Incoming Interface : 0x58( 0x58 ) <-- Ss (Slice source)
For Outgoing Interface
module-1(DBG-elam-insel6)# report | grep ovec
hom_elam_out_sidebnd_no_spare_vec.ovector_idx: 0x40
leaf1# show lldp neighbors int eth1/52
Device ID Local Intf Hold-time Capability Port ID
Spine1 Eth1/52 120 BR Eth1/29
========================
Spine1
========================
debug platform internal roc elam asic 0
trigger reset
trigger init in-select 14 out-select 1
set inner ipv4 src_ip 192.168.11.11 dst_ip 192.168.12.12
start
module-1(DBG-elam-insel14)# status
ELAM STATUS
===========
Asic 0 Slice 0 Status Triggered
Asic 0 Slice 1 Status Armed
Asic 0 Slice 2 Status Armed
Asic 0 Slice 3 Status Armed
module-1(DBG-elam-insel14)# ereport
Python available. Continue ELAM decode with LC Pkg
ELAM REPORT
======================================================================================================================================================
Trigger/Basic Information
======================================================================================================================================================
ELAM Report File : /tmp/logs/elam_2024-06-29-18m-16h-32s.txt
In-Select Trigger : Outer(l2(vntag)|l3|l4)-inner(l2|l3|l4)-ieth( 14 )
Out-Select Trigger : Pktrw-sideband-drpvec( 1 )
ELAM Captured Device : SPINE_SC
Packet Direction : egress
Triggered ASIC type : Bigsky
Triggered ASIC instance : 0
Triggered Slice : 0
Incoming Interface : 0x58( 0x58 )
( Slice Source ID(Ss) in "show plat int hal l2 port gpd" )
Packet from vPC peer LEAF : yes
Packet from tunnel (remote leaf/avs) : yes
======================================================================================================================================================
Captured Packet
======================================================================================================================================================
------------------------------------------------------------------------------------------------------------------------------------------------------
Outer Packet Attributes
------------------------------------------------------------------------------------------------------------------------------------------------------
Outer Packet Attributes : l2uc ipv4 ip ipuc ipv4uc udp ivxlan
Opcode : OPCODE_UC
------------------------------------------------------------------------------------------------------------------------------------------------------
Outer iEth Header
------------------------------------------------------------------------------------------------------------------------------------------------------
iEth SUP code : NONE
Packet from CPU : no
------------------------------------------------------------------------------------------------------------------------------------------------------
Outer L2 Header
------------------------------------------------------------------------------------------------------------------------------------------------------
Destination MAC : 000D.0D0D.0D0D
Source MAC : 000C.0C0C.0C0C
802.1Q tag is valid : yes
CoS : 0
Access Encap VLAN : 2
VN-Tag is valid : no
<-- ( FC tells LC via Vn-Tag about which port the packet needs to go to )
Src VIF (in from leaf/IPN) : 0
<-- ( VIF(dec) in ELTMC or LID(hex) in "show plat int hal l2 port pi" )
Dst VIF (out to leaf/IPN) : 0
<-- ( OIFL in "show forwarding multicast outgoing-interface-list 0" )
------------------------------------------------------------------------------------------------------------------------------------------------------
Inner L2 Header
------------------------------------------------------------------------------------------------------------------------------------------------------
Inner Destination MAC : 000C.0C0C.0C0C
Source MAC : 000C.0C0C.0C0C
802.1Q tag is valid : no
CoS : 0
Access Encap VLAN : 0
------------------------------------------------------------------------------------------------------------------------------------------------------
Outer L3 Header
------------------------------------------------------------------------------------------------------------------------------------------------------
L3 Type : IPv4
DSCP : 0
Don't Fragment Bit : 0x0
TTL : 32
IP Protocol Number : UDP
Destination IP : 10.0.248.0
Source IP : 10.0.32.69
------------------------------------------------------------------------------------------------------------------------------------------------------
Inner L3 Header
------------------------------------------------------------------------------------------------------------------------------------------------------
L3 Type : IPv4
DSCP : 0
Don't Fragment Bit : 0x0
TTL : 254
IP Protocol Number : ICMP
Destination IP : 192.168.12.12
Source IP : 192.168.11.11
module-1(DBG-elam-insel14)# show platform internal hal l2 port gpd
Incoming interface
Incoming Interface : 0x58( 0x58 )
Outgoing interface
module-1(DBG-elam-insel14)# report | grep ovec
bky_elam_out_sidebnd_no_spare_vec.ovector_idx: 0x148
module-1(DBG-elam-insel14)# show platform internal hal l2 port gpd | grep 148
1a000000 Eth1/1 0 2 3 0 2a 2 9 48 148 1 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 D-24d - 100 0 1 1 2 0 0
spine1# show lldp neighbors interface ethernet 1/1
Capability codes:
Device ID Local Intf Hold-time Capability Port ID
leaf3 Eth1/1 120 BR Eth1/49
========================
Leaf3
========================
debug platform internal tah elam asic 0
trigger reset
trigger init in-select 14 out-select 1
set inner ipv4 src_ip 192.168.11.11 dst_ip 192.168.12.12
start
module-1(DBG-elam-insel14)# status
ELAM STATUS
===========
Asic 0 Slice 0 Status Armed
Asic 0 Slice 1 Status Triggered
module-1(DBG-elam-insel14)# ereport
Python available. Continue ELAM decode with LC Pkg
ELAM REPORT
======================================================================================================================================================
Trigger/Basic Information
======================================================================================================================================================
ELAM Report File : /tmp/logs/elam_2024-06-29-24m-16h-34s.txt
In-Select Trigger : Outer(l2(vntag)|l3|l4)-inner(l2|l3|l4)-ieth( 14 )
Out-Select Trigger : Pktrw-sideband-drpvec( 1 )
ELAM Captured Device : LEAF
Packet Direction : egress
Triggered ASIC type : Sugarbowl
Triggered ASIC instance : 0
Triggered Slice : 1
Incoming Interface : 0x38( 0x38 )
( Slice Source ID(Ss) in "show plat int hal l2 port gpd" )
Packet from vPC peer LEAF : yes
Packet from tunnel (remote leaf/avs) : yes
======================================================================================================================================================
Captured Packet
======================================================================================================================================================
------------------------------------------------------------------------------------------------------------------------------------------------------
Outer Packet Attributes
------------------------------------------------------------------------------------------------------------------------------------------------------
Outer Packet Attributes : l2uc ipv4 ip ipuc ipv4uc udp ivxlan
Opcode : OPCODE_UC
------------------------------------------------------------------------------------------------------------------------------------------------------
Outer iEth Header
------------------------------------------------------------------------------------------------------------------------------------------------------
iEth SUP code : NONE
Packet from CPU : no
------------------------------------------------------------------------------------------------------------------------------------------------------
Outer L2 Header
------------------------------------------------------------------------------------------------------------------------------------------------------
Destination MAC : 000C.0C0C.0C0C
Source MAC : 0000.0000.0000
802.1Q tag is valid : yes
CoS : 0
Access Encap VLAN : 2
VN-Tag is valid : no
<-- ( FC tells LC via Vn-Tag about which port the packet needs to go to )
Src VIF (in from leaf/IPN) : 0
<-- ( VIF(dec) in ELTMC or LID(hex) in "show plat int hal l2 port pi" )
Dst VIF (out to leaf/IPN) : 0
<-- ( VIF(dec) in ELTMC or LID(hex) in "show plat int hal l2 port pi" )
-------------------------------------------------------------------------------------------------------------------------------
Inner L2 Header
-------------------------------------------------------------------------------------------------------------------------------
Inner Destination MAC : 000C.0C0C.0C0C
Source MAC : 000C.0C0C.0C0C
802.1Q tag is valid : no
CoS : 0
Access Encap VLAN : 0
------------------------------------------------------------------------------------------------------------------------------------------------------
Outer L3 Header
------------------------------------------------------------------------------------------------------------------------------------------------------
L3 Type : IPv4
DSCP : 0
Don't Fragment Bit : 0x0
TTL : 32
IP Protocol Number : UDP
Destination IP : 10.0.32.67
Source IP : 10.0.32.69
------------------------------------------------------------------------------------------------------------------------------------------------------
Inner L3 Header
------------------------------------------------------------------------------------------------------------------------------------------------------
L3 Type : IPv4
DSCP : 0
Don't Fragment Bit : 0x0
TTL : 254
IP Protocol Number : ICMP
Destination IP : 192.168.12.12
Source IP : 192.168.11.11
module-1(DBG-elam-insel14)# show platform internal hal l2 port gpd
Incoming Packet
Incoming Interface : 0x38( 0x38 )
Outgoing Interface
module-1(DBG-elam-insel14)# report | grep ovec
sug_elam_out_sidebnd_no_spare_vec.ovector_idx: 0x20
======================
Traffic from leaf3 to leaf1
=======================
debug platform internal tah elam asic 0
trigger reset
trigger init in-select 6 out-select 1
set outer ipv4 src_ip 192.168.12.12 dst_ip 192.168.11.11
start
status
ereport
================================================
L2 traffic
================================================
vsh_lc
deb pla in <tah/roc/app> elam asic 0
trigger init in-select 6 out-select 1
set out l2 src-mac <Mac> dst-mac <mac address>
start
status
ereport
===============================================
The 'ereport' command can be used to display ELAM results in a clear and easy-to-understand format.
ELAM reports are saved in the /var/log/dme/log/ directory on the switch. Each ELAM capture generates two files:
elam_<timestamp>.txt
pretty_elam_<timestamp>.txt
ftriage
Leaf # ftriage bridge -ii LEAF:104 -dmac 02:02:02:02:02:02
Leaf # ftriage route -ii LEAF:203,204 -sip 10.100.13.100 -dip 10.88.156.30
This command is using ftriage in its “route” mode. Here’s a breakdown of the components:
ftriage routeThis tells the tool to perform a routing query.
-ii LEAF:203,204The -ii flag specifies the interface indices. In this case, it targets the interfaces labeled “LEAF:203” and “LEAF:204.” These identifiers likely refer to specific network segments or physical interfaces that are part of the analysis.
-sip 10.100.13.100The -sip flag indicates the source IP address for the routing query. This is the IP from which the traffic originates.
-dip 10.88.156.30The -dip flag specifies the destination IP address. This is where the traffic is intended to go.
In summary, this command tells ftriage to check the routing path between the source IP (10.100.13.100) and the destination IP (10.88.156.30) while specifically considering the interfaces LEAF:203 and LEAF:204.
The output will likely show how packets are routed between these points across the given interfaces, which can be useful for troubleshooting connectivity or configuration issues in your network.
Comments