diff --git a/internal/aghslog/aghslog.go b/internal/aghslog/aghslog.go
index 9fdce880..c307f344 100644
--- a/internal/aghslog/aghslog.go
+++ b/internal/aghslog/aghslog.go
@@ -41,7 +41,7 @@ const (
 	UpstreamTypeService = "service"
 
 	// UpstreamTypeTest is the log attribute value for upstreams used for
-	// testing.
+	// testing and validation.
 	UpstreamTypeTest = "test"
 )
 
diff --git a/internal/client/persistent.go b/internal/client/persistent.go
index fc925442..1d1967a2 100644
--- a/internal/client/persistent.go
+++ b/internal/client/persistent.go
@@ -10,6 +10,7 @@ import (
 	"slices"
 	"strings"
 
+	"github.com/AdguardTeam/AdGuardHome/internal/aghslog"
 	"github.com/AdguardTeam/AdGuardHome/internal/filtering"
 	"github.com/AdguardTeam/dnsproxy/proxy"
 	"github.com/AdguardTeam/dnsproxy/upstream"
@@ -143,7 +144,7 @@ func (c *Persistent) validate(ctx context.Context, l *slog.Logger, allTags []str
 	}
 
 	conf, err := proxy.ParseUpstreamsConfig(c.Upstreams, &upstream.Options{
-		Logger: slogutil.NewDiscardLogger(),
+		Logger: l.With(aghslog.KeyUpstreamType, aghslog.UpstreamTypeTest),
 	})
 	if err != nil {
 		return fmt.Errorf("invalid upstream servers: %w", err)