From da483dca8f3619dcb6d798b00b1172af8cfda5b8 Mon Sep 17 00:00:00 2001
From: Roman Dodin <dodin.roman@gmail.com>
Date: Mon, 22 Nov 2021 21:26:03 +0100
Subject: [PATCH] do not regen ceos system mac file

---
 nodes/ceos/ceos.go | 10 ++++++++--
 utils/file.go      |  1 +
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/nodes/ceos/ceos.go b/nodes/ceos/ceos.go
index 8952a5fb2..3f65123c6 100644
--- a/nodes/ceos/ceos.go
+++ b/nodes/ceos/ceos.go
@@ -138,8 +138,14 @@ func createCEOSFiles(node *types.NodeConfig) error {
 		return err
 	}
 	m[5] = m[5] + 1
-	utils.CreateFile(path.Join(node.LabDir, "flash", "system_mac_address"), m.String())
-	return nil
+
+	sysMacPath := path.Join(node.LabDir, "flash", "system_mac_address")
+
+	if !utils.FileExists(sysMacPath) {
+		err = utils.CreateFile(sysMacPath, m.String())
+	}
+
+	return err
 }
 
 // ceosPostDeploy runs postdeploy actions which are required for ceos nodes
diff --git a/utils/file.go b/utils/file.go
index 1fd7f9503..5cfdeada7 100644
--- a/utils/file.go
+++ b/utils/file.go
@@ -18,6 +18,7 @@ var errNonRegularFile = errors.New("non-regular file")
 var errFileNotExist = errors.New("file does not exist")
 var errHTTPFetch = errors.New("failed to fetch http(s) resource")
 
+// FileExists returns true if a file referenced by filename exists
 func FileExists(filename string) bool {
 	f, err := os.Stat(filename)
 	if os.IsNotExist(err) {