---
title: "Histogram per Capture Port"
slug: "packet-tricks-histogram-per-capture-port"
updated: 2025-03-26T04:22:19Z
published: 2025-03-26T04:22:19Z
canonical: "docs.fmad.io/packet-tricks-histogram-per-capture-port"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://docs.fmad.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Histogram per Capture Port

Getting a quick histogram on the per physical capture ports can be quite helpful when configuring and patching a system

## Step 1) Locate the capture file

Using the command

```plaintext
fmadiocli "show capture list"
```

The system will output a list of captures. example shown below

```plaintext
fmadio@fmadio200v4-636:$ fmadiocli "show capture list"
fmad fmadlua Mar 19 2025 (/opt/fmadio/bin/fmadiolua --nocal /opt/fmadio/bin/fmadiocli show capture list )
Disable cycle calibration
[Wed Mar 26 12:13:03 2025] CmdLine [show capture list]
[Wed Mar 26 12:13:03 2025] Cmd [show capture list ]
[Wed Mar 26 12:13:03 2025] Showing captures
[Wed Mar 26 12:13:03 2025] [wan0_20250325_0000                                                              ]      148,361,445,376 B (Tue . 23:29:07 . 25-03-2025)
[Wed Mar 26 12:13:03 2025] [wan0_20250324_0000                                                              ]      176,206,381,056 B (Mon . 23:59:58 . 24-03-2025)
[Wed Mar 26 12:13:03 2025] [wan0_20250323_0000                                                              ]      124,999,958,528 B (Sun . 23:59:58 . 23-03-2025)
[Wed Mar 26 12:13:03 2025] [wan0_20250322_0000                                                              ]      126,681,088,000 B (Sat . 23:59:59 . 22-03-2025)
[Wed Mar 26 12:13:03 2025] [wan0_20250321_0000                                                              ]      698,711,015,424 B (Fri . 23:59:59 . 21-03-2025)
[Wed Mar 26 12:13:03 2025] [wan0_20250320_0000                                                              ]      253,637,951,488 B (Fri . 00:00:00 . 21-03-2025)
.
.
[Wed Mar 26 12:13:03 2025] [ny2_election_10AM_20250205_1619                                                 ]    5,218,116,829,184 B (Thu . 00:00:01 . 07-11-2024)
[Wed Mar 26 12:13:03 2025] [opra_election_20250125_2231                                                     ]    3,273,740,517,376 B (Wed . 23:00:01 . 06-11-2024)
done 0.084506Sec 0.001408Min
fmadio@fmadio200v4-636:$
```

Locate the capture to be analyized. In this example we have selected the capture named

```plaintext
wan0_20250320_0000
```

## Step 2) Run the processing

Using the above capture name run the command

```plaintext
sudo stream_cat -v --chunked <capture name> | capinfos2 --histo-port
```

This sequence will process the data at roughly 20Gbps sustained, example output is shown below

```plaintext
fmadio@fmadio200v4-636:~$ sudo stream_cat -v --chunked wan0_20250320_0000                                                               | capinfos2 --histo-port
Enable Port Histogram
Chunked Packet output
stream_cat ioqueue: 4
TimeStamp[0] --pcap
TimeStamp[1] --pcap
TimeStamp[2] --pcap
TimeStamp[3] --pcap
TimeStamp[4] --pcap
TimeStamp[5] --pcap
TimeStamp[6] --pcap
TimeStamp[7] --pcap
FMAD Format Chunked
[20250326_121833]  0M Offset:    0GB ChunkID:21662485 TS:16:00:00.563.411.315 | Pending 241888 MB 4.459Gbps 0.870Mpps CPUIdle:0.000 CPUFetch:0.198 CPUSend:0.586
[20250326_121834]  3M Offset:    2GB ChunkID:21671120 TS:16:30:01.875.979.087 | Pending 239729 MB 17.666Gbps 3.445Mpps CPUIdle:0.000 CPUFetch:0.198 CPUSend:0.720
[20250326_121835]  6M Offset:    4GB ChunkID:21679726 TS:16:59:24.888.737.559 | Pending 237578 MB 17.607Gbps 3.433Mpps CPUIdle:0.000 CPUFetch:0.197 CPUSend:0.721
[20250326_121836]  10M Offset:    6GB ChunkID:21688300 TS:17:27:31.139.125.623 | Pending 235434 MB 17.541Gbps 3.421Mpps CPUIdle:0.000 CPUFetch:0.197 CPUSend:0.722
.
.
```

In the above we see there is 241GB “Pending” as the capture size is about 250GB and its processing at 17Gbps.

## Step 3) Results

Once the process has completed (or partial process with Ctrl-C) the Histogram data is shown below

```plaintext
Total Packets: 44532390
TotalBytes     : 28500729600
TotalPackets   : 44532390
PayloadCRC     : 524b6a016f940129
ErrorSeq       : 0
ErrorPktSize   : 0
LastByte       : 0x00000000
SeqStart       : 0x00000000 0x00000000 0x00000000 0x00000000 : 0x00000000
SeqEnd         : 0x00000000 0x00000000 0x00000000 0x00000000 : 0x00000000
PacketCnt      : 0 0 0 0
TimeOrder      : 0
CRCFail        : 0
CRCFailFNIC    : 0
Time First     : 20250319_235959 15:59:59.803.989.459 (1742399999.803989459)
Time Last      : 20250320_062310 22:23:10.047.420.435 (1742422990.047420435)
TotalPCAPTime  : 22990243430976 ns (383.171min)
Bandwidth      : 0.010 Gbps
Packet Rate    : 0.002 Mpps

Port Histogram:
  Port:0 Pkt:           0 Byte:           0
  Port:1 Pkt:    44532390 Byte: 28500729600
  Port:2 Pkt:           0 Byte:           0
  Port:3 Pkt:           0 Byte:           0
  Port:4 Pkt:           0 Byte:           0
  Port:5 Pkt:           0 Byte:           0
  Port:6 Pkt:           0 Byte:           0
  Port:7 Pkt:           0 Byte:           0
```

In the above case, we see all of the packets are on physical capture port 1.