Localhost connections give "connection refused" errors

[douglasg14b]

Running from the CLI, localhost connections give a connection refused error.

{
    "iteration_count": 30000,
    "debug" : false,
    "load_type": "linear",
    "duration": 30,
    "steps": [
        {
            "id": 1,
            "url": "http://localhost:5228/api/v1/analytics/event",
            "method": "POST",
            "headers": {
                "Content-Type": "application/json"
            },
            "payload": "{\"eventData\":{\"type\":\"action\",\"name\":\"ButtonClick_SendVerificationButton\",\"buttonName\":\"back\"},\"context\":{\"scope\":\"EnterMDNDialog_SendVerificationButton\",\"scopes\":[\"EnterMDNDialog\",\"SendVerificationButton\"],\"app\":{\"appName\":\"my-app\",\"appPath\":\"\/my-app\",\"version\":2},\"device\":{\"os\":\"Windows\",\"browser\":\"Firefox\"},\"identities\":{\"deviceId\":\"abcd-1234\",\"customerId\":\"abcd-1234\"},\"extra\":{\"isSubscriber\":true,\"identifiedBy\":\"asurion-id\",\"verificationType\":\"MDN\",\"componentType\":\"BUTTON\"},\"meta\":{\"isTest\":true,\"artificial\":true}}}",
            "timeout": 2
        }
    ]
}

[fatihbaltaci]

Hi @douglasg14b, are you using the Docker version of Ddosify?

[douglasg14b]

Nope, the command line version.

[cdong8812]

same issue here using latest version, and it looks like ddosify doesn't honor keep-alive even if it is set in the config via "keep-alive": true, I am using the config based cli, even after increasing ulimit on my mac to 128k I still see the test starts failing after a short time, even with load of 10k request over 20s, it doesn't make sense to use that many connections to send so little qps, consider based on the code here: https://github.com/ddosify/ddosify/blob/master/core/scenario/requester/http.go#L434, the MaxIdleConnsPerHost is hardcoded as 60000

[fatihbaltaci]

Hi @douglasg14b, I could not reproduce this issue.

I started a nginx server on my machine:

docker run -it --rm -p 8080:80 nginx

I can access it from a web browser with http://localhost:8080

Then I used Ddosify to test the nginx endpoint:

➜  ~ ddosify -version
Version:        v0.13.2
Git commit:     6e3511d
Built           2023-02-06T09:51:34Z
Go version:     go1.18.10
OS/Arch:        darwin/arm64

➜  ~
➜  ~ ddosify -t http://localhost:8080
⚙️  Initializing...
🔥 Engine fired.

🛑 CTRL+C to gracefully stop.
✔️  Successful Run: 14     100%       ❌ Failed Run: 0        0%       ⏱️  Avg. Duration: 0.00423s
✔️  Successful Run: 29     100%       ❌ Failed Run: 0        0%       ⏱️  Avg. Duration: 0.00296s
^C✔️  Successful Run: 33     100%       ❌ Failed Run: 0        0%       ⏱️  Avg. Duration: 0.00300s


RESULT
-------------------------------------
Success Count:    33    (100%)
Failed Count:     0     (0%)

Durations (Avg):
  DNS                  :0.0000s
  Connection           :0.0000s
  Request Write        :0.0001s
  Server Processing    :0.0028s
  Response Read        :0.0001s
  Total                :0.0030s

Status Code (Message) :Count
  200 (OK)    :33

The status code is 200. Then I tried with your config file and changed the URL to nginx. Again, I did not get connection refused error.

Please give me some details of your target server to reproduce this issue. Thanks.

[ghost]

Hi @douglasg14b, are you using the Docker version of Ddosify?

Hi @fatihbaltaci, apologies for sort of hijacking this issue. What would be the solution when using the Docker version?

[fatihbaltaci]

Hi @zvdbit, you can add --network host when using Ddosify in Docker. Here is an example:

docker run -it --rm --network host ddosify/ddosify ddosify -t http://localhost:8080

Ddosify can access http://localhost:8080 server.

[douglasg14b]

The target server in my case is Kestrel, a C# Asp.Net Core project ran in debug mode.

[ghost]

Hi @zvdbit, you can add --network host when using Ddosify in Docker. Here is an example:

docker run -it --rm --network host ddosify/ddosify ddosify -t http://localhost:8080

Ddosify can access http://localhost:8080 server.

Thanks, the --network host resolves the issue.

[fatihbaltaci]

Hi @cdong8812, we released a new version of Ddosify v0.15.0. In this release:

• We removed the keep-alive option from the config file. You can set the Connection header for each step.
• We introduced the engine_mode option. You can set engine_mode to distinct-user in your config file if you want Ddosify to use the existing connection between steps (keep-alive) and different connections between iterations.

You can find the details in the config file section. Thanks.

[strangedev]

FWIW, I experienced similar issues, and found that I was running out of local ports, since the default port range on linux only allows for ~28k outbound connections.

In my case, setting sysctl net.ipv4.ip_local_port_range="1024 61000" during testing helped.