From 58e27dec10b51b5c9d3efe0faa9ebae15c506023 Mon Sep 17 00:00:00 2001
From: Alexander Dahl <alex@netz39.de>
Date: Thu, 27 Feb 2025 13:38:29 +0100
Subject: [PATCH] :bug: Use bash as shell in cron jobs to make process
substitution work
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The cron jobs were executed, but dash (/bin/sh) complained, and so the
actual command was never run. This is why our dyndns update did not
work through cron, but when executed manually in bash by an admin.
Example for such a fail when done manually in sh:
# echo test3 > >(/usr/bin/logger -p user.debug -t dd24)
/bin/sh: 7: Syntax error: redirection unexpected
Process substitution with `>(command)` is a feature supported by bash
and other shells, but not by POSIX shell which was supposed to used here
(set by `SHELL=…`). Instead of building complicated redirect magic for
sh just switch to bash, which should be available on the hosts affected.
Link: https://www.shellcheck.net/wiki/SC3001
Fixes: 03dbd132ebc5 (":loud_sound: Send DD24 cron errors to syslog")
Fixes: 38fbff30b5c5 ("feat: add role to manage dyndns entry on desec.io")
---
roles/dd24_dyndns_cron/templates/dd24-dyndns.cron.j2 | 2 +-
roles/desec_dyndns_cron/templates/desec-dyndns.cron.j2 | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/roles/dd24_dyndns_cron/templates/dd24-dyndns.cron.j2 b/roles/dd24_dyndns_cron/templates/dd24-dyndns.cron.j2
index 8e01809..fb60772 100644
--- a/roles/dd24_dyndns_cron/templates/dd24-dyndns.cron.j2
+++ b/roles/dd24_dyndns_cron/templates/dd24-dyndns.cron.j2
@@ -1,6 +1,6 @@
# /etc/cron.d/dd24-dyndns: Cron call to renew DynDNS entry
-SHELL=/bin/sh
+SHELL=/bin/bash
PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
*/5 * * * * root curl --silent --show-error "https://dynamicdns.key-systems.net/update.php?hostname={{dyndns_domain}}&password={{dyndns_password}}&ip={{dyndns_ip}}" > /dev/null 2> >(/usr/bin/logger -p user.error -t dd24)
diff --git a/roles/desec_dyndns_cron/templates/desec-dyndns.cron.j2 b/roles/desec_dyndns_cron/templates/desec-dyndns.cron.j2
index 32bf8b6..2d2ca02 100644
--- a/roles/desec_dyndns_cron/templates/desec-dyndns.cron.j2
+++ b/roles/desec_dyndns_cron/templates/desec-dyndns.cron.j2
@@ -1,6 +1,6 @@
# /etc/cron.d/desec-dyndns: Cron call to renew DynDNS entry
-SHELL=/bin/sh
+SHELL=/bin/bash
PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
*/5 * * * * root curl --silent --show-error --user {{ dyndns_domain }}:{{ dyndns_token }} "https://update.dedyn.io/" > /dev/null 2> >(/usr/bin/logger -p user.error -t desec)