Bug Description
Hello everyone and team, from time to time i'm experiencing some weird behaviour with the returning .IP() value.
I'm using nginx in front, having this config
proxy_http_version 1.1;
proxy_set_header Host $http_host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto $scheme;
proxy_set_header X-Scheme $scheme;
proxy_set_header X-Forwarded-Uri $request_uri;
And in the app i have a simple rate-limit function
router := fiber.New(fiber.Config{
ProxyHeader: "X-Real-IP",
TrustProxy: true,
TrustProxyConfig: fiber.TrustProxyConfig{
Loopback: true,
Private: true,
},
})
router.Use(logger.New(logger.Config{
Format: "[${time}] ${ip} - ${status} - ${latency} - ${protocol} ${method} ${url} - ${error}\n",
Stream: os.Stdout,
Next: func(f fiber.Ctx) bool {
return websocket.IsWebSocketUpgrade(f) || f.IsWebSocket() || f.Path() == strings.TrimRight(c.Config.API.Path, "/")+"/health"
},
}))
ws := router.Group(c.Config.API.PathWS)
ws.Use("/", func(f fiber.Ctx) error {})
ws.Get("/", func(f fiber.Ctx) error {
if websocket.IsWebSocketUpgrade(f) {
return f.Next()
}
return fiber.ErrUpgradeRequired
}, handler.Events())
api := router.Group(c.Config.API.Path)
api.Use(handler.RateLimit)func (c *Config) RateLimit(f fiber.Ctx) error {
if !c.Config.API.RateLimit.Enabled || websocket.IsWebSocketUpgrade(f) || f.IsWebSocket() {
return f.Next()
}
guestIP := f.IP()
log.Println("_" + guestIP + "_")
// the rest of the logic for either update or add the values / guest
}
func (c *Config) CleanupRateLimits() {
if !c.Config.API.RateLimit.Enabled {
return
}
// logic here to the 'removed' variable
for _, addr := range removed {
c.Log.Add(logging.Entry{
Notice: fmt.Sprintf("-> Guest '%s' was automatically cleaned out", addr),
})
}
}I have added some logging to debug it further, and from time to time i see this in the logs
2026/04/10 04:04:32 54.37.168.222
2026/04/10 04:05:03 89.125.209.209
[04:05:03] 89.125.209.209 - 404 - 151.407µs - HTTP/1.1 GET /xmlrpc.php - -
2026/04/10 04:05:25 165.227.7.228
[04:05:25] 165.227.7.228 - 404 - 165.952µs - HTTP/1.1 GET /xmlrpc.php - -
[04:05:26] 165.227.7.228 - 404 - 110.085µs - HTTP/1.1 GET /wp-login.php - -
2026/04/10 04:05:26 165.227.7.228
2026/04/10 05:05:26 [HANDLERS/RATE_LIMIT:232] -> Guest '54.37.168.222' was automatically cleaned out
2026/04/10 05:05:26 [HANDLERS/RATE_LIMIT:232] -> Guest '89.125.209.209' was automatically cleaned out
2026/04/10 05:05:26 [HANDLERS/RATE_LIMIT:232] -> Guest 'websocket.228' was automatically cleaned out
Somehow the value of f.IP() is becoming websocket.228 and my assumption is that would be for the 165.227.7.228 IP as the other ones above were correctly addressed. I really can not understand what is this exactly.
How to Reproduce
Code added above
Expected Behavior
Returning the correct IP value
Fiber Version
v3.1.0
Code Snippet (optional)
package main
import "github.com/gofiber/fiber/v3"
import "log"
func main() {
app := fiber.New()
// Steps to reproduce
log.Fatal(app.Listen(":3000"))
}Checklist:
Bug Description
Hello everyone and team, from time to time i'm experiencing some weird behaviour with the returning .IP() value.
I'm using nginx in front, having this config
And in the app i have a simple rate-limit function
I have added some logging to debug it further, and from time to time i see this in the logs
Somehow the value of
f.IP()is becomingwebsocket.228and my assumption is that would be for the165.227.7.228IP as the other ones above were correctly addressed. I really can not understand what is this exactly.How to Reproduce
Expected Behavior
Returning the correct IP value
Fiber Version
v3.1.0
Code Snippet (optional)
Checklist: