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--- soc:2009:pravin:journal:fedora11bko [2009/07/04 15:17]
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+++ soc:2009:pravin:journal:fedora11bko [2009/07/27 05:35] (current)
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 It seems, fedora wants something to be set for ''/dev/root'' and another thing that I need to find out is what is this ''JBD'' error about ''barrier-based sync failed''
+==== /dev/root ====
+''/dev/root: error opening volume''  is handled, I just looked for various places where ''/dev/root'' is used and wrapped it with ''if [-z ${HTTPFS}]'' \\
+now I need to find out what is that JBD problem
+==== JBD problem ====
+I initially doubted function ''do_live_overlay'' but it is clean,
+now, concentrating parent function ''do_live_from_base_loop'' function.
+<code>
+mount -n -o ro,remount /dev/mapper/live-rw /sysroot
+</code>
+is giving above JBD related errors. But this is not fatal, it is continuing even after this
+But it seems there might be problems in run-init script
+===== solution =====
+Finally, problem is solved, there was one more reference to ''plymouth'' that I had to comment out
+Most of the plymouth references where options.  Means even the command fails, the execution will not stop
+<code>
+plymouth --show-splash || :
+</code>
+but there was one perticular reference, which was not made optional.  I dont know if it is intentional or error.
+may be, problem is in ''run-init'' script
+===== Next problem =====
+The graphical mode and run level 3 are not booting.  There is some problem in sendmail daemon, which is causing segementation fault which just freezes the execution and I get kernel panic.  I will try with disabling sendmail and see if it works.\\
+Here is the error
+<code>
+Starting Bluetooth services:                                 [ OK ]
+EXT-4-fs error (device dm-0): ext4_find_entry: reading #13191 offset 0
+/etc/rc.d/rc : line 100 : /etc/rc3.d/S80sendmail: Input/output error
+</code>
+and so on....
+=== solution ===
+I disabled sendmail and tried.  It partially worked. There was some error which I could not see because of scrolling, but then it gave login prompt.
+The problem is, when I press enter key, it takes it as ''^M'', so I am not able to login :-(
+=== attempt 2 ===
+Disabled selinux with ''selinux=0'' and tried again\\
+I removed sendmail and other services which were related to S99 like firstboot, local.
+but still I am getting error
+<code>
+EXT4-fs error (device dm-0): __ext4_get_inode_loc: unable to read inode block - inode=9642, block=827
+</code>
+There is one warning regarding device dm-0 while boot time, I am not sure if that is relevant to this error, but I will anyway document it here
+<code>
+JDB: barrier-based sync failed on dm-0:8 - disabling barriers
+</code>
+and following are the logs from apache2 server which was serving this iso image.
+<code>
+$ cat /var/log/apache2/access.log | tail
+.168.0.1 - - [06/Jul/2009:23:56:27 +0200] "GET /Fedora-11-i686-Live.iso HTTP/1.1" 206 4096 "-" "-"
+.168.0.1 - - [06/Jul/2009:23:56:27 +0200] "GET /Fedora-11-i686-Live.iso HTTP/1.1" 206 16384 "-" "-"
+.168.0.1 - - [06/Jul/2009:23:56:27 +0200] "GET /Fedora-11-i686-Live.iso HTTP/1.1" 206 32768 "-" "-"
+.168.0.1 - - [06/Jul/2009:23:56:27 +0200] "GET /Fedora-11-i686-Live.iso HTTP/1.1" 206 65536 "-" "-"
+.168.0.1 - - [06/Jul/2009:23:56:27 +0200] "GET /Fedora-11-i686-Live.iso HTTP/1.1" 206 131072 "-" "-"
+.168.0.1 - - [06/Jul/2009:23:56:27 +0200] "GET /Fedora-11-i686-Live.iso HTTP/1.1" 206 131072 "-" "-"
+.168.0.1 - - [06/Jul/2009:23:56:27 +0200] "GET /Fedora-11-i686-Live.iso HTTP/1.1" 206 4096 "-" "-"
+.168.0.1 - - [06/Jul/2009:23:56:27 +0200] "GET /Fedora-11-i686-Live.iso HTTP/1.1" 206 16384 "-" "-"
+.168.0.1 - - [06/Jul/2009:23:56:27 +0200] "GET /Fedora-11-i686-Live.iso HTTP/1.1" 206 32768 "-" "-"
+.168.0.1 - - [06/Jul/2009:23:56:27 +0200] "GET /Fedora-11-i686-Live.iso HTTP/1.1" 206 65536 "-" "-"
+</code>
+I am not sure if they will make any sense, but I have put them for reference.
+===== Attempt-3 =====
+I wanted to remove ''/etc/rc3.d/S80sendmail'', but I am not able to delete it. It says it is read-only filesystem.
+But when I run mount command, it shows the filesystem in ''rw'' mode.  Following are the command I tried.
+<code>
+# mount
+/dev/root on / type ext4 (rw,noatime)
+proc on /proc type proc (rw)
+/sys on /sys type sysfs (rw)
+udev on /dev type tmpfs (rw,mode=0755)
+/dev/pts on /dev/pts type devpts (rw,gid=5,mode=620)
+# rm /sysroot/etc/rc3.d/S80sendmail
+rm: cannot remove '/sysroot/etc/rc3.d/S80sendmail' : Read-only file system
+# mount / -o remount,rw
+# rm /sysroot/etc/rc3.d/S80sendmail
+rm: cannot remove '/sysroot/etc/rc3.d/S80sendmail' : Read-only file system
+</code>
+====== What is working?  ======
+Single user mode is working fine.  so user gets shell where he can do all he wants
+====== Fedora 11 live over NFS ======
+Trying to see if Fedora 11 live can boot over NFS.\\
+The reasoning behind this experimentation is that, if it works over NFS then it may help in locating the problem.
+==== Testing NFS setup ====
+Exported the "/var/www" ( because it contains all the ISO images) over NFS.  Following is the excerpt from ''/etc/exports''
+<code>
+/var/www *(ro,async)
+</code>
+This NFS volume does get mounted properly on local machine.
+<code>
+sudo mount 192.168.111.11:/var/www mpoint
+$ mount
+.168.111.11:/var/www on /home/pravin/Etherboot/mpoint type nfs (rw,addr=192.168.111.11)
+</code>
+==== Testing the NFS mount from virtualization ====
+Fedora 11 live cd was booted with virtualBox. The network was working and even the host machine was accissible as the URL http://192.168.111.11 did correctly resolved to Host website.\\
+But NFS mount failed with following error.
+<code>
+# mount 192.168.111.11:/var/www /home/liveuser/mpoint/
+mount.nfs: access denied by server while mounting 192.168.111.11:/var/www
+</code>
+Why would this fail if mounting from localhost is working fine?
+Got help from rwrc, and fixed the problem.\\
+It seems one more option has to be added to export options ''insecure'', restating the explanation given by rwcr
+<code>
+rwcr: Try making it /var/www *(ro,async,insecure)
+rwcr: Linux generally requires NFS requests to come from privileged ports, and the Fedora livecd might be using a nonstandard NFS mounter that doesn't do that.
+</code>
+===== Next step : mount NFS partition from initramfs =====
+Debian uses special program called ''nfsmount'' for NFS mounting at boot time, I will try out both. The mount command and nfsmount utility.\\
+Also, the kernel module be needed.
+Following modules and executable ''/sbin/mount.nfs'' was needed for NFS to work
+   - sunrpc.ko
+   - lockd.ko
+   - auth_rpcgss.ko
+   - nfs_acl.ko
+   - nfs.ko
+In addition to this, I had to pass option ''-o nolock'' for mount to work without problems
+<code>
+mount "${NFS_PATH} /iso -o nolock"
+mount /iso/Fedora-11-i686-Live.iso /sysroot -o loop -o ro
+</code>
+NFS works fine in run level 3. also one can start the GUI with ''startx'' after logging in as ''root'' from multiuser prompt.\\
+The only issue with NFS_Fedora is that ''plymountd'' still creates a problem and is disabled and it somehow stops GUI coming up automatically.\\
+So, the user need to login in run-level 3 and then do the ''startx''
+==== HTTPFS improvement ====
+Some progress has been done on HTTPFS front also.  Till now, all the tests of booting over HTTPFS were done using ''qemu'' which is inherently slow as it is emulation.
+When same tests were run on vmware, which is much faster, errors started comming after runlevel - 3 login prompt\\
+Following are the errors, which are quite same as those errors which use to come around sendmail daemon before.
+<code>
+# startx
+-bash: /usr/bin/startx: Input/output error
+# top
+top : error while loading shared libraries: /lib/libncursesw.so.5: cannot read file data: Input/output error
+EXT4-fs error (device dm-0): ext4_find_entry: reading directory #10651 offset 0
+</code>
+With this observation, we can claim that errors are thrown because there is delay in response from fuse.  The ext4-fs is giving up because of this delay.\\
+Now, I need to find a way to increase the tolerance for this delay.
+===== Removing plymouth =====
+As marc has suggested, remove ''plymount'' from original iso, and see if it works without plymount.
+If it doesn't then blame can be surely put on ''plymount'' and not the network related complications. \\
+==== Modifying ISO ====
+Now, the question is, how to add new initramfs into ISO and still keep it bootable?\\
+From Remastering Knoppix Howto, following is the command which works for knoppix
+<code>
+mkisofs -pad -l -r -J -v -V "KNOPPIX" -no-emul-boot -boot-load-size 4 \
+   -boot-info-table -b boot/isolinux/isolinux.bin -c boot/isolinux/boot.cat \
+   -hide-rr-moved -o /mnt/hda1/knx/knoppix.iso /mnt/hda1/knx/master
+</code>
+and I need to modify it, so that it will work for fedora.
+<code>
+mkisofs -pad -l -r -J -v -V "Fedora-11-i686-Live" -no-emul-boot -boot-load-size 4 \
+   -boot-info-table -b isolinux/isolinux.bin -c isolinux/boot.cat \
+   -hide-rr-moved -o /var/www/iso/fedora_11.iso /home/pravin/Etherboot/git/BKO.git/pxeknife/red_hat/fedora_11_live_cd/newfedora
+</code>
+===== running startx from single user mode =====
+Tried an experiment of running ''startx'' from single user mode and see if it works.\\
+Well it did not worked atall.
+===== Problem Found =====
+With help of andyTim, the cause of problem has been located.\\
+The ''network'' and ''NetworkManager'' do restart the networking which breaks the existing HTTPFS mount.
+===== Solution =====
+The temporary solution tried is delete both of following files
+  - ''/etc/init.d/network''
+  - ''/etc/init.d/NetworkManager''
+So, user has to first boot into single user mode, delete above files,
+and then boot into runlevel 5.

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