From d32d15df38269f7fc0df6cad2774b0f50119fea4 Mon Sep 17 00:00:00 2001
From: Christian Theune <ct@flyingcircus.io>
Date: Thu, 26 Sep 2024 07:32:05 +0200
Subject: [PATCH] nfs: switch to hard recovery to avoid potential data
 consistency issues

We discovered that soft ist a sub-optimal setting but was initially
set due to recovery issues. Having investigated the current issue
we decided to switch back to hard.

Re PL-133015
---
 nixos/roles/nfs.nix | 14 +++++++++++---
 tests/nfs.nix       | 13 ++++++++++++-
 2 files changed, 23 insertions(+), 4 deletions(-)

diff --git a/nixos/roles/nfs.nix b/nixos/roles/nfs.nix
index 3edbdcd4f..1de84f360 100644
--- a/nixos/roles/nfs.nix
+++ b/nixos/roles/nfs.nix
@@ -73,15 +73,23 @@ in
 
     (lib.mkIf (cfg.roles.nfs_rg_client.enable && service != null) {
       fileSystems = {
-        # WARNING: those settings are duplicated in the tests to
-        # fix a deficiency of the test harness.
         "${mountpoint}" = {
           device = "${service.address}:${export}";
           fsType = "nfs4";
+          #############################################################
+          # WARNING: those settings are DUPLICATED in tests/nfs.nix to
+          # work around a deficiency of the test harness.
+          #############################################################
           options = [
             "rw"
             "noauto"
-            "soft"
+            # Retry infinitely
+            "hard"
+            # Start over the retry process after 10 tries
+            "retrans=10"
+            # Start with a 3s (30 deciseconds) interval and add 3s as linear
+            # backoff
+            "timeo=30"
             "rsize=8192"
             "wsize=8192"
             "nfsvers=4"
diff --git a/tests/nfs.nix b/tests/nfs.nix
index 8bd3744a0..de2e9cb60 100644
--- a/tests/nfs.nix
+++ b/tests/nfs.nix
@@ -59,9 +59,20 @@ in {
             "${cdir}" = {
               device = "server:${sdir}";
               fsType = "nfs4";
+              ################################################################
+              # WARNING: those settings are DUPLICATED in nixos/roles/nfs.nix
+              # to work around a deficiency of the test harness.
+              ################################################################
               options = [
                 "rw"
-                "soft"
+                "noauto"
+                # Retry infinitely
+                "hard"
+                # Start over the retry process after 10 tries
+                "retrans=10"
+                # Start with a 3s (30 deciseconds) interval and add 3s as linear
+                # backoff
+                "timeo=30"
                 "rsize=8192"
                 "wsize=8192"
                 "nfsvers=4"