From: Thierry Parmentelat <thierry.parmentelat@inria.fr>
Date: Fri, 8 Jul 2016 09:41:58 +0000 (+0200)
Subject: when resolv.conf is empty, always add 8.8.8.8
X-Git-Tag: bootcd-5.4-1~3
X-Git-Url: http://git.onelab.eu/?p=bootcd.git;a=commitdiff_plain;h=ed5ce94453595611f867aa26801094938cc690bd

when resolv.conf is empty, always add 8.8.8.8
on top of DNS1 and DNS2
---

diff --git a/fedoras.md b/fedoras.md
new file mode 100644
index 0000000..2cdf712
--- /dev/null
+++ b/fedoras.md
@@ -0,0 +1,4 @@
+A few notes on the status wrt recent fedoras
+
+# `/etc/resolv.conf`
+
diff --git a/initscripts/pl_functions b/initscripts/pl_functions
index 72878d6..30b035d 100644
--- a/initscripts/pl_functions
+++ b/initscripts/pl_functions
@@ -40,6 +40,8 @@ function verbose-forensics () {
     verbose-run lsmod
     verbose-run lspci
     
+    # XXX : need to check for a running udev
+
     for file in /etc/resolv.conf /run/resolvconf/resolv.conf /etc/sysconfig/network-scripts/ifcfg-eth*; do 
 	verbose-file $file
     done
diff --git a/initscripts/pl_netinit b/initscripts/pl_netinit
index 2363cea..ae9dbea 100755
--- a/initscripts/pl_netinit
+++ b/initscripts/pl_netinit
@@ -283,7 +283,7 @@ fi
 # tmp: Thierry June 2015
 # on fedora 21 nodes we see this running in a context where eth0 is not known to the system
 # could be related to a dependency that we poorly describe to systemd
-# I am increasing this timeout to 2 minutes in order to check that conjecture
+# I am increasing this timeout to 1 minute in order to check that conjecture
 ALLOW=60
 COUNTER=0
 while true; do
@@ -321,30 +321,36 @@ verbose-message "pl_netinit: attempting to start networking"
 
 verbose-message "pl_netinit: network online"
 
-# patch for f22 - if /etc/resolv.conf is empty in static mode
+# patch for f22 and above - if /etc/resolv.conf is empty or missing
 function pl-netinit-patch-resolv-conf () {
-    file=/etc/resolv.conf
+    file="$1"; shift
     needed=""
     # missing file : patch needed
     if ! [ -f $file ]; then
 	needed=true
     # empty file : patch needed
-    elif cmp $file /dev/null; then
-	needed=true
-    fi
-    if [ -n "$needed" ]; then
-	verbose-message "pl_netinit: patching $file"
-	source /etc/sysconfig/network-scripts/ifcfg-${ETH_DEVICE}
-	# delete because it's a symlink to /run/systemd/resolve/resolv.conf
-	# which looks really weird (ls -lL /etc/resolv.conf does not show anything)
-	rm $file
-	( [ -n "$DNS1" ] && echo nameserver $DNS1; \
-	  [ -n "$DNS2" ] && echo nameserver $DNS2 ) > $file
     else
+	contents=$(grep -v '^#' $file)
+	contents=$(echo $contents)
+	[ -z "$contents" ] && needed=true
+    fi
+    if [ -z "$needed" ]; then
 	echo pl_netinit has no need to patch $file
+	return
     fi
+
+    verbose-message "pl_netinit: patching $file"
+    source /etc/sysconfig/network-scripts/ifcfg-${ETH_DEVICE}
+    # delete because it may be a symlink to /run/systemd/resolve/resolv.conf
+    # which looks really weird (ls -lL /etc/resolv.conf does not show anything)
+    rm -f $file
+    # mention the DNS servers defined in the config - if any
+    [ -n "$DNS1" ] && echo nameserver $DNS1 >> $file
+    [ -n "$DNS2" ] && echo nameserver $DNS2 >> $file
+    # also add landmark for good measure
+    echo "nameserver 8.8.8.8" >> $file
 }
 
-pl-netinit-patch-resolv-conf
+pl-netinit-patch-resolv-conf /etc/resolv.conf
 
 verbose-forensics "pl_netinit epilogue"
diff --git a/initscripts/pl_sysinit b/initscripts/pl_sysinit
index 630b9f0..492cc73 100755
--- a/initscripts/pl_sysinit
+++ b/initscripts/pl_sysinit
@@ -15,11 +15,16 @@ verbose-message "pl_sysinit: bringing system online"
 verbose-message "pl_sysinit: mounting file systems"
 verbose-run /bin/mount -v -a
 
+# on old systems that use init, we totally take control and replace
+# /etc/inittab with just our stuff, so nothing is going to run udev
+# for us and we need to start it ourselves
 if [ -x /sbin/start_udev ]; then
     verbose-message "pl_sysinit: starting udev daemon"
     verbose-run /sbin/start_udev
 else
-    verbose-message "pl_sysinit: WARNING cannot start udev daemon - /sbin/start_udev NOT FOUND"
+    # on systemd-based systems, udev is triggered by systemd
+    # but just in case we issue a warning
+    verbose-message "pl_sysinit: WARNING cannot start udev daemon (probably safe under systemd)"
 fi
 
 verbose-message "pl_sysinit: invoking hardware initialization script"
diff --git a/outline.md b/outline.md
new file mode 100644
index 0000000..31900e2
--- /dev/null
+++ b/outline.md
@@ -0,0 +1,24 @@
+# overall sequence (sysV init / systemd)
+
+* `pl_sysinit`
+* `pl_boot`
+
+# `pl_sysinit`
+
+* udev
+* **PY** `pl_hwinit`
+  * loads modules / blacklisted
+  * modprobe `sd_mod`, `usb_storage`, `floppy`
+  * wait 10' for USB subsystem to come up
+* initrd
+* block-devices
+* device-mapper-node
+* sysctl
+* rsyslog
+* **SH** `pl_netinit`
+  * locate network config
+  * IPMI 
+  * determine interface name<>
+* clock
+
+# `pl_boot`