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coop

coop

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  • Posts: 28
  • Member Since: 19 Nov 09
  • Last Logged In: 6 days ago

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  • coop
    RE: LFS201 LAB 37.3
    It means turn on debugging, which means echoing all commands to the console *before* they are executed, essentially it means verbose. You turn off this debug mode with set +x. This is all buried somewhere in the man page for bash, not set. It is also discussed in the "debugging" section of the bash chapter I'm pretty sure, but I don't have the class in front of me. so you often do: set -x ... some commands set +x when you want to get more detailed output, often but not exclusively, while debugging a script.
    Link to this post 6 days ago

    It means turn on debugging, which means echoing all commands
    to the console *before* they are executed, essentially it means verbose.
    You turn off this debug mode with set +x. This is all buried somewhere in the man
    page for bash, not set. It is also discussed in the "debugging" section of the
    bash chapter I'm pretty sure, but I don't have the class in front of me.

    so you often do:

    set -x

    ... some commands

    set +x

    when you want to get more detailed output, often but not exclusively, while debugging
    a script.

  • coop
    RE: LFS201 Lab 10.1 problem on CentOS7-VMWARE
    "none" did not help me, and adding "verbose" to the kernel command line actually made things worse somehow. "verbose" is *not* a kernel parameters AFAIK; all of them are listed in DOcumentation/kernel-parameters.txt in the kernel source, and in kernel documentation parameters, and developers are pretty careful to put all parameters in that document, do that they are all explained and can be used. (I should search the source, but it will be hard to find where a parameter such as that is parsed). However, any parameter not understood by the kernel is passed to "init" (in this case systemd-init) and I have to see what that does with the parameter. In any case, it did not work for me anyway. So I'll take this as homework, but I'm rather busy right now, might even be a week or weeks before I can think about it.
    Link to this post 09 Jul

    "none" did not help me, and adding "verbose" to the kernel command line actually made things worse somehow.

    "verbose" is *not* a kernel parameters AFAIK; all of them are listed in DOcumentation/kernel-parameters.txt in the kernel source, and in kernel documentation parameters, and developers are pretty careful to put all parameters in that document, do that they are all explained and can be used. (I should search the source, but it will be hard to find where a parameter such as that is parsed). However, any parameter not understood by the kernel is passed to "init" (in this case systemd-init) and I have to see what that does with the parameter.

    In any case, it did not work for me anyway. So I'll take this as homework, but I'm rather busy right now, might even be a week or weeks before I can think about it.

  • coop
    RE: Possible errors in LFS201 Ch 40. Firewalls
    The first and last bullet point are not in the master copies, which I thought were already uploaded (they were already fixed). Thanks for the others
    Link to this post 09 Jul

    The first and last bullet point are not in the master copies, which I thought were already uploaded (they were already fixed). Thanks for the others

  • coop
    RE: LFS201 Lab 10.1 problem on CentOS7-VMWARE
    This lab was probably only tested on CentOS6, not CentOS7. They are rather different at least in the sense RHEL6 uses Grub 1, RHEL7 uses Grub 2. However, i reviewed all the official red hat instructions for RHEL7 and the only thing that is not right is there should be a third argument of "none" in /etc/crypttab, i.e., secret-disk /dev/sda4 none to encourage it to prompt for a password. However I don't think this is the problem. Also, I do not know what you mean by you added "verbose" to the kernel command line as that is not a normal kernel parameter. Anyway, if anyone knows the answer fine, let us know. Otherwise we'll investigate, it is time consuming and we'll start by trying fedora, ubuntu etc. Thanks for bringing this to our attention
    Link to this post 09 Jul

    This lab was probably only tested on CentOS6, not CentOS7. They are rather different at least in the sense RHEL6 uses Grub 1, RHEL7 uses Grub 2. However, i reviewed all the official red hat instructions for RHEL7 and the only thing that is not right is there should be a third argument of "none" in /etc/crypttab, i.e.,

    secret-disk /dev/sda4 none

    to encourage it to prompt for a password. However I don't think this is the problem. Also, I do not know what you mean by you added "verbose" to the kernel command line as that is not a normal kernel parameter.

    Anyway, if anyone knows the answer fine, let us know. Otherwise we'll investigate, it is time consuming and we'll start by trying fedora, ubuntu etc.
    Thanks for bringing this to our attention

  • coop
    RE: Lab 4.1 fake_service.txt
    The file is broken, it is not worth figuring out. I thought it was fixed in the class but it wasn't, we'll try and take care of it.
    Link to this post 09 Jul

    The file is broken, it is not worth figuring out. I thought it was fixed in the class but it wasn't, we'll try and take care of it.

  • coop
    RE: Course language changed from English to Spanish
    We apologize for the mixup, it should be fixed within a few hours at most. When the Spanish version went live, the English version was inadvertently displaced. Thanks for calling this promptly to our attention!
    Link to this post 02 Jul

    We apologize for the mixup, it should be fixed within a few hours at most.

    When the Spanish version went live, the English version was inadvertently displaced.

    Thanks for calling this promptly to our attention!

  • coop
    RE: Offline Course Material
    Hi: I'm afraid it is not possible to download a soft copy of the class. However, you can download all the labs and solutions and work on them. You have probably noticed that at the beginning of the book there is a reference to one big file that contains all labs and solutions, do you don't have to download a zillion files one by one.
    Link to this post 23 Jun

    Hi:

    I'm afraid it is not possible to download a soft copy of the class.

    However, you can download all the labs and solutions and work on them. You have probably noticed that at the beginning of the book there is a reference to one big file that contains all labs and solutions, do you don't have to download a zillion files one by one.

  • coop
    RE: 16.8 Examples of Rezising (LVM )
    As to what happens with your lvreduce command, try it and you'll find out. fsadm does not resize the partition, only the filesystem size. so you would have to run lvextend and then fsadm, or fsadm and then lvreduce in that order, instead.
    Link to this post 01 Jun

    As to what happens with your lvreduce command, try it and you'll find out.

    fsadm does not resize the partition, only the filesystem size.
    so you would have to run lvextend and then fsadm, or fsadm
    and then lvreduce in that order, instead.

  • coop
    RE: Lab 13.1 swapon failed: Invalid argument
    I did the exact same thing and it worked just fine. THe warnings are just that, but they don't affect the result, if you do cat /proc/swaps you see it is there. However, googling says it may depend on the filesystem type the swapfile is sitting on. In particular, btrfs apparently doesn't go for it. see http://superuser.com/questions/539287/swapon-failed-invalid-argument-on-a-linux-system-with-btrfs-filesystem Perhaps that is the problem? I didn't know of this until I scoured around.
    Link to this post 26 May

    I did the exact same thing and it worked just fine. THe warnings are just that,
    but they don't affect the result, if you do cat /proc/swaps you see it is there.

    However, googling says it may depend on the filesystem type the swapfile is sitting on.
    In particular, btrfs apparently doesn't go for it. see

    http://superuser.com/questions/539287/swapon-failed-invalid-argument-on-a-linux-system-with-btrfs-filesystem

    Perhaps that is the problem? I didn't know of this until I scoured around.

  • coop
    RE: Lab 4.1 fake_service.txt
    Yes you right :( I have confirmed it. It seems the online platform converted to Windows end of line characteristics (old problem). There are 3 other download files in the course (writeit.c signals.c ioscript.sh) that are affected as well, but while they have changed end of line characters, they look ok. We'll get them fixed in the next release. There doesn't seem to be a way to post a file here in the forum (probably wise) but if you go to http://training.linuxfoundation.org/cm/LFS201, and log in with: username LFtraining password: Penguin2014, you can download all the files directly.
    Link to this post 12 May

    Yes you right :( I have confirmed it. It seems the online platform converted to Windows end of line characteristics (old problem). There are 3 other download files in the course (writeit.c signals.c ioscript.sh) that are affected as well, but while they have changed end of line characters, they look ok. We'll get them fixed in the next release.

    There doesn't seem to be a way to post a file here in the forum (probably wise) but if you go to http://training.linuxfoundation.org/cm/LFS201, and log in with: username LFtraining password: Penguin2014, you can download all the files directly.

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