verify_qdisc: Use a random IFB name to prevent collisions

With parallel startup of SQM instances, always using the same name for testing if an IFB works leads to collisions and failures. Instead, use a random IFB name each time, which should hopefully be enough to avoid collisions. Fixes tohojo#120. Signed-off-by: Toke Høiland-Jørgensen <[email protected]>
ldir-EDB0 · May 23, 2020 · 0dcd5f5 · 0dcd5f5
1 parent a0626e0
commit 0dcd5f5
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/src/functions.sh b/src/functions.sh
@@ -384,9 +384,11 @@ verify_qdisc() {
     local args
     local IFB_MTU
     local found
+    local randnum
     qdisc=$1
     supported="$2"
-    ifb=TMP_IFB_4_SQM
+    randnum=$(tr -cd 0-9a-f < /dev/urandom | head -c 5)
+    ifb=SQM_IFB_$randnum
     root_string="root" # this works for most qdiscs
     args=""
     IFB_MTU=1514