cmd: Better error handling when reloading (#6601)

* caddyhttp: Limit auto-HTTPS error logs to 100 domains

* Improve error message and increase error size limit

3 files changed, 6 insertions, 2 deletions

diff --git a/cmd/commandfuncs.go b/cmd/commandfuncs.go
index 50e9b110d..a5c357cd7 100644
--- a/cmd/commandfuncs.go
+++ b/cmd/commandfuncs.go
@@ -716,7 +716,7 @@ func AdminAPIRequest(adminAddr, method, uri string, headers http.Header, body io
 
 	// if it didn't work, let the user know
 	if resp.StatusCode >= 400 {
-		respBody, err := io.ReadAll(io.LimitReader(resp.Body, 1024*10))
+		respBody, err := io.ReadAll(io.LimitReader(resp.Body, 1024*1024*2))
 		if err != nil {
 			return nil, fmt.Errorf("HTTP %d: reading error message: %v", resp.StatusCode, err)
 		}
diff --git a/modules/caddyhttp/autohttps.go b/modules/caddyhttp/autohttps.go
index ea5a07b3c..79fdfd6ec 100644
--- a/modules/caddyhttp/autohttps.go
+++ b/modules/caddyhttp/autohttps.go
@@ -732,7 +732,7 @@ func (app *App) automaticHTTPSPhase2() error {
 	)
 	err := app.tlsApp.Manage(app.allCertDomains)
 	if err != nil {
-		return fmt.Errorf("managing certificates for %v: %s", app.allCertDomains, err)
+		return fmt.Errorf("managing certificates for %d domains: %s", len(app.allCertDomains), err)
 	}
 	app.allCertDomains = nil // no longer needed; allow GC to deallocate
 	return nil
diff --git a/modules/caddytls/tls.go b/modules/caddytls/tls.go
index 5f3d0eaeb..f04beb2ee 100644
--- a/modules/caddytls/tls.go
+++ b/modules/caddytls/tls.go
@@ -447,6 +447,10 @@ func (t *TLS) Manage(names []string) error {
 	for ap, names := range policyToNames {
 		err := ap.magic.ManageAsync(t.ctx.Context, names)
 		if err != nil {
+			const maxNamesToDisplay = 100
+			if len(names) > maxNamesToDisplay {
+				names = append(names[:maxNamesToDisplay], fmt.Sprintf("(%d more...)", len(names)-maxNamesToDisplay))
+			}
 			return fmt.Errorf("automate: manage %v: %v", names, err)
 		}
 		for _, name := range names {