George Udosen's questions

I am working on Vagrant on my Ubuntu (20.04) and I learnt that the ip range allowed by default is 192.168.56.0/21 and that I can of course remove this restriction and use my own range.

I am new to vagrant and know if they are any inherent or severe results to use the /etc/vbox/networks.conf to set my own ip range. I am looking at using the ranges:

- 192.168.0.0/16
- 10.0.0.0/8
- 2001::/64

Apart from ip address conclusions for already created virtualbox machines why would this be a good or bad idea. I want to be able to set any ip address for my vagrant boxes for learning purposes.

I am currently running Ubuntu Focal Fossa and trying to ssh into an OpenSuSe machine version being openSUSE Leap 15.2. I can ssh into every other machine using the Bridge Network configuration but for the said machine I get a

ssh: connect to host 10.64.40.206 port 22: No route to host

error. I can even ping the machine but can't just ssh into it. Perhaps there's a configuration setting expected on the Host to be able to ssh into OpenSuSe.

I am trying to log iptables actions so I can trouble shoot why a FORWARD rule isn't working and I need to run this command:

echo ipt_LOG >/proc/sys/net/netfilter/nf_log/2

this is after loading the logging module "sudo modprobe ipt_LOG" and I keep getting this error even when I have switch to root (sudo -i) and am in the location of the said file '2':

root@george-jendoc-node:/proc/sys/net/netfilter/nf_log# echo "ipt_LOG" > 2
-bash: echo: write error: No such file or directory

I did a stat 2 and I got:

File: 2
  Size: 0               Blocks: 0          IO Block: 1024   regular empty file
Device: 4h/4d   Inode: 185636      Links: 1
Access: (0644/-rw-r--r--)  Uid: (    0/    root)   Gid: (    0/    root)
Access: 2020-05-12 12:27:05.420721533 +0000
Modify: 2020-05-12 12:33:44.449767903 +0000
Change: 2020-05-12 12:33:44.449767903 +0000
 Birth: -

I clearly see the file in question but why am I getting the 'no such file or directory' error and how do I write to that file?

UPDATE:

cat 2 shows NONE and echo ipt_LOG shows 'ipt_LOG'.

I am trying to get my firewalld to block an ip address with the rules:

• sudo firewall-cmd --zone=block --add-source=<ip_address/submask> --permanent, and also adding this richrule to the default zone (public)
• sudo firewall-cmd --permanent --add-rich-rule='rule family="ipv4" source address=<ip_address> reject, then finally I reload the rule with sudo firewall-cmd --reload

But still I can navigate to the sites in my browser. Obviously I am doing some thing wrong. How can I block access to any webpage using firewalld.

These are my zone rules set:

block (active)
  interfaces: enp0s3
  sources: 172.217.5.110/32 216.49.176.33/32
  services: 
  ports: 
  protocols: 
  masquerade: no
  forward-ports: 
  icmp-blocks: 
  rich rules: 


public (default, active)
  interfaces: docker0
  sources: 
  services: dhcpv6-client ssh
  ports: 993/tcp 995/udp 995/tcp 22161/udp 4243/tcp 22/tcp 22/udp 465/tcp
  protocols: 
  masquerade: no
  forward-ports: 
  icmp-blocks: 
  rich rules: 

I am trying understand what the difference is between two ways of creating a loop mount point. Now I can create this with:

1. sudo mount -o loop /file_to_use /mntpoint, and

2. sudo losetup /dev/loop1 /file_to_use and then mount sudo mount /dev/loop1 /mntpoint

Question:

Are these the two processes the same as I have tested them and there both result in the same mount points as seen here, but I could be wrong?

NAME   FSTYPE LABEL UUID                                 MOUNTPOINT
sda                                                      
├─sda1 ext4         7af461fe-8d2d-4499-a12a-72ff586ff5d6 /boot
├─sda2 swap         44744c25-8797-4cd2-b83e-f129e97efc85 [SWAP]
├─sda3 ext4         3d39068d-96da-4f90-be42-b0921fb7278e /
└─sda4 ext4         643c8738-9823-43cd-b2b2-efe0b81b7611 /home
sr0                                                      
loop0  ext4         ac7deda8-7f3b-4835-8308-e4020ffe5302 /mnt/vfs
loop1  ext4         68a0676b-ad59-4dff-9c50-eca5d972c1c7 /mnt/tempdir

I am trying to create a logical volume partition using parted and so I used the following steps:

1. Create partition with parted using the interactive mode which would translate to:

   • mkpart, then
   • Gave the start and end
   • Then ran set 1 lvm on to flag that partition as lvm (but I see lsb)

2. Tried to create a physical volume with command:

   sudo pvcreate /dev/sda4
   

I get the error: device /dev/sda4 excluded by a filter, then I ran the pvcreated command with the options -vvvv and I see the error:

skipping too small to hold a pv

I now ran fdisk on /dev/sda and I see the /dev/sda4 partition information as:

/dev/sda4:=> id:f, Type: W95 Ext'd(LBA)

This is different from the information for the other logical volume partitions I have, which is:

/dev/sda3:=> id:8e, Type: Linux LVM

Now the new LVM partition /dev/sda4 is approximately the same size as the other so why can't I create a physical volume. How does one create a logical volume partition using parted as opposed to fdisk.

I tried installing Ubuntu 18.04 and and it failed to install grub2 and I lost my former OS as I had used the (Ubuntu) iso file to install from the grub menu as my BIOS won't let me boot from a usb stick.

Now I was able to re-install Ubuntu Xenial ( which was previously there ), but my laptop says it can't see a bootable device and I should install an OS. I can boot using the boot from UEFI file option and I see this output from my efibootmgr:

$ sudo efibootmgr -v

BootCurrent: 003D
BootOrder: 0000,3000,2001,2002,2003
Boot0000* ubuntu    HD(1,GPT,8ccf22f4-daf3-4aa6-80af-1a7ed10b68dd,0x800,0x100000)/File(\EFI\ubuntu\shimx64.efi)
Boot2001* USB Drive (UEFI)  RC
Boot2002* Internal CD/DVD ROM Drive (UEFI)  RC
Boot3000* Internal Hard Disk or Solid State Disk    RC
Boot3001* Internal Hard Disk or Solid State Disk    RC
Boot3002* Internal Hard Disk or Solid State Disk    RC
Boot3003* Internal Hard Disk or Solid State Disk    RC

I noticed I have this: BootCurrent: 003D, I was expecting to see Boot**** so I am not sure what 003D means and how to get my system to boot normally.

I have tried several options as suggested:

https://ubuntuforums.org/showthread.php?t=2147295,

https://ubuntuforums.org/showthread.php?t=2238714

This is my /boot/efi folder structure after doing as instructed in the links above:

.
└── EFI
    ├── Boot
    │   └── bootmgfw.efi
    ├── Microsoft
    │   └── Boot
    │       └── bootmgfw.efi
    └── ubuntu
        ├── fw
        ├── fwupx64.efi
        ├── grub.cfg
        ├── grubx64.efi
        ├── mmx64.efi
        └── shimx64.efi

And I also noticed that I get this results when I try to run the following commands:

sudo efibootmgr -c -L "UEFI Hard Drive" -l "\EFI\Boot\bootx64.efi"

efibootmgr: Could not set variable Boot0001: No such file or directory
efibootmgr: Could not prepare boot variable: No such file or directory

Obviously I am missing a file or directoryneeded byefibootmgr`.

This is my partition scheme:

NAME   FSTYPE   LABEL UUID                                 MOUNTPOINT
sda                                                        
├─sda1 vfat           7086-1111                            /boot/efi
├─sda2 ext4           69a49ce7-993e-4fc3-8ad1-062041b7e411 /
└─sda3 swap           340dd345-6ac1-4772-b014-9e508124b371 [SWAP]

And from sudo gdisk /dev/sda:

Number  Start (sector)    End (sector)  Size       Code  Name
   1            2048         1050623   512.0 MiB   EF00  EFI System Partition
   2         1050624      1936889855   923.1 GiB   8300  
   3      1936889856      1953523711   7.9 GiB     8200  

Running sudo efibootmgr -c -L "Windows Boot Manager" -l "\EFI\Boot\shimx64.efi" gives the following errors:

efibootmgr: Could not set variable Boot0001: No such file or directory
efibootmgr: Could not prepare boot variable: No such file or directory

Update:

I am still trying to restore my normal boot behaviour and I used the command sudo bootctl --path /boot/efi status and I got this result:

Failed to read EFI variable LoaderDevicePartUUID: No such file or directory
System:
     Firmware: n/a (n/a)
  Secure Boot: disabled
   Setup Mode: user

Loader:
      Product: n/a
    Partition: n/a
         File: └─n/a

Boot Loader Binaries:
          ESP: /dev/disk/by-partuuid/570d26cf-ecca-489b-849b-e1a562b99226
systemd-boot not installed in ESP.
         File: └─/EFI/Boot/bootmgfw.efi

Boot Loader Entries in EFI Variables:
        Title: ubuntu
           ID: 0x0000
       Status: active, boot-order
    Partition: /dev/disk/by-partuuid/8ccf22f4-daf3-4aa6-80af-1a7ed10b68dd
         File: └─/EFI/ubuntu/shimx64.efi

Can someone help with interpretation?

I have added the tree layout of the /boot/efi folder, can some one tell me if anything is off:

.
├── EFI
│   ├── BOOT
│   │   ├── bootmgfw.efi
│   │   └── BOOTX64.EFI
│   ├── Microsoft
│   │   └── bootmgfw.efi
│   ├── systemd
│   │   └── systemd-bootx64.efi
│   └── ubuntu
│       ├── fw
│       ├── fwupx64.efi
│       ├── grub.cfg
│       ├── grubx64.efi
│       ├── mmx64.efi
│       └── shimx64.efi
└── loader
    ├── entries
    └── loader.conf

I have this situation where I want to exclude a directory while using the mv command. I saw this example where the syntax would be !(exclude_dir), but when I set up a scenario to test it I get results that I don't fully understand.

Now I have created three folders: f1,f2 and f3. Now I use the command in this way:

mv -t f3/ !(f1) f2

This produces this error:

mv: cannot move 'f3' to a subdirectory of itself, 'f3/f3'
mv: cannot stat 'f2': No such file or directory

Now funny thing is the structure of the folder is now:

.
├── f1
└── f3
    └── f2

3 directories, 0 files

It does what I want but why the error messages. Obviously I am not using that command correctly.

I noticed that when I triple click (with mouse) to select text (or a command) from say a website, and then paste this into my terminal using Ctrl+Alt+v, then the command runs immediately (i.e. it automatically inputs Enter key), but if I select(with mouse) and copy the same command and use Ctrl+Alt+v to paste it into the terminal it does not auto-run the code but it rather just pastes it and awaits input from me before the code will run.

Which mechanism makes this so? Because I would rather first look at the command to be run before running it, but I noticed this will be done for me any time I use triple click to select a word.

I have this strange behaviour where if I access the Grub2 recovery mode and select the the recovery menu option Drop to root shell prompt and mount the file system with:

mount -o remount,rw /

After moving between folder with cd command, if I stop entering commands at the prompt for a few seconds it begins to load or starting certain services on its own without me actually exiting the prompt and resuming normal boot. I see the error:

failed to start lsb

It then return to the recovery menu and freezes with my inability to re-select any option from the recovery menu using my keyboard, after that it shows the error:

sulogin: input overrun at /dev/tty1

From here on I can only shutdown the guest OS from virtualbox.

NAME      TYPE      SIZE USED PRIO
/dev/dm-1 partition 4.7G   0B   -1
george@george-ubuntu-server:~$ df -h
Filesystem                                   Size  Used Avail Use% Mounted on
udev                                         2.3G     0  2.3G   0% /dev
tmpfs                                        469M  7.5M  462M   2% /run
/dev/mapper/george--ubuntu--server--vg-root   36G   10G   24G  30% /
tmpfs                                        2.3G  216K  2.3G   1% /dev/shm
tmpfs                                        5.0M  4.0K  5.0M   1% /run/lock
tmpfs                                        2.3G     0  2.3G   0% /sys/fs/cgroup
/dev/sda1                                    472M  165M  284M  37% /boot
cgmfs                                        100K     0  100K   0% /run/cgmanager/fs
leap                                         909G  568G  342G  63% /media/sf_leap
tmpfs                                        469M   44K  469M   1% /run/user/1000

george@george-ubuntu-server:~$ sudo blkid

/dev/sda1: UUID="1a047c26-dce8-4e9f-bb18-d06f03135c7a" TYPE="ext2" PARTUUID="7576c720-01"
/dev/sda5: UUID="4hGUQE-38qc-M27B-5u0Z-cWST-4E1l-jfOEYF" TYPE="LVM2_member" PARTUUID="7576c720-05"
/dev/mapper/george--ubuntu--server--vg-root: UUID="d9741b12-2158-4d81-8fbb-8256b31b99ea" TYPE="ext4"
/dev/mapper/george--ubuntu--server--vg-swap_1: UUID="6a97a99c-78df-4a30-aec9-815e9b62dcc9" TYPE="swap"

george@george-ubuntu-server:~$ cat /etc/fstab

# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
/dev/mapper/george--ubuntu--server--vg-root /               ext4    errors=remount-ro 0       1
# /boot was on /dev/sda1 during installation
UUID=1a047c26-dce8-4e9f-bb18-d06f03135c7a /boot           ext2    defaults        0       2
/dev/mapper/george--ubuntu--server--vg-swap_1 none            swap    sw              0       0

dpkg -l *lsb* | grep ii

ii  lsb-base       9.20160110ubuntu0.2 all          Linux Standard Base init script functionality
ii  lsb-release    9.20160110ubuntu0.2 all          Linux Standard Base version reporting utility

grep -i lsb /var/log/syslog*

Results link: http://pastebin.com/07brqwXC

george@george-HP-Pavilion-17-Notebook-PC:~$ lsb_release -a

No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 16.04.1 LTS
Release:    16.04
Codename:   xenial

Virtualbox version:

VirtualBox Graphical User Interface
Version 5.1.14 r112924 (Qt5.5.1)

Update:

tail -f /var/log/syslog

Note: can't copy text

I am learning Linux system administration and I noticed that if I do

sudo systemctl poweroff

on my Ubuntu Xenial, it carries out the command far faster than it would if I did the same using the shutdown button from the GUI.

From the little I have done with Linux, this seems to be the case with most commands.

My understanding (I could be wrong being a system admin in the making) is that the off button also calls the systemctl poweroff command. This I inferred from the way the apt tool works as it calls the underlying dpkg when running a task.

I would think the time difference shouldn't be very noticeable but it is.

I am learning linux system administration on ubuntu trusty and I had to create logical volumes from two partitions created off the disk in the ubuntu VM.

Now this is how it went:

sudo pvcreate /dev/sda3
sudo pvcreate /dev/sda4

sudo vgcreate myvg /dev/sda3 /dev/sda4

sudolvcreate -L 300M -n mylvm myvg

sudo mkdir mylvm

sudo mkfs.ext4 /dev/myvg/mylvm

sudo mount /dev/myvg/mylvm /mylvm

sudo lvextend -L 350M /dev/myvg/mylvm

Then added this to /etc/fstab

/dev/myvg/mylvm /mylvm ext4 defaults 0 0 

Now if I run lsblk I see this:

NAME                  MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda                     8:0    0    40G  0 disk 
├─sda1                  8:1    0    18G  0 part /
├─sda2                  8:2    0     1K  0 part 
├─sda3                  8:3    0   3.9G  0 part 
│ └─myvg-mylvm (dm-0) 252:0    0   352M  0 lvm  /mylvm
├─sda4                  8:4    0   4.8G  0 part 
└─sda5                  8:5    0     2G  0 part [SWAP]
sr0                    11:0    1  1024M  0 rom 

Now why is the /dev/sda3 the only physical volume with the assigned size, would have thought /dev/sda4 would also have a branch too. Perhaps I have not understood how LVM works. A good explanation would really clear me.

I have been given a task to creat a LUKS encrypted partition and then mount it, here are the steps I followed:

1. Create the partition for encryption:

   sudo fdisk /dev/sda
   

2. Reboot

3. Format the partition with cryptsetup:

   sudo cryptsetup luksFormat /dev/sda3
   

4. Open encrypted partition:

   sudo cryptsetup luksOpen /dev/sda3 secret-disk
   

5. Add the following to /etc/crypttab:

   secret-disk       /dev/sda3
   

6. Make filesystem on partition:

   sudo mkfs -t ext3 /dev/mapper/secret-disk
   

7. Make mount directory:

   sudo mkdir /secret
   

8. Add the following to /etc/fstab:

   /dev/mapper/secret-disk   /secret   ext4 defaults 1 2
   

9. Mount partition at /secret:

   sudo mount /secret OR sudo mount -a
   

10. Reboot.

Problem: During reboot, the mount instruction in fstab returns the error : device not ready or not present. And I have to enter S to skip the mount so ubuntu can boot or M to recover it manually. I have checked this option but it does not solve mine. How do I get the encrypted partition to mount at /secret.

I have this code:

#!/bin/bash 

#clear screen
clear 

# Ask for name of directory to create
echo "Please enter a directory name"
echo "that you wish to create"
read dir1

# create directory
mkdir $dir1

# change to the newly created directory
cd $dir1

# Tell user where he/she is
echo "This directory is called 'pwd'"


# create some files
touch file1 file2 file3


# put in some content 
echo "This is $dir1/file1" > file1
echo "This is $dir1/file2" > file2
echo "This is $dir1/file3" > file3



# announce file names
echo "The files in $dir1 are: "
ls -hl

# show the contents  of the files
echo "The content of the files are: "
cat file1
cat file2
cat file3


echo "Goodbye"

The line with echo "This directory is called 'pwd'" refuses to give the current working directory as expected. Please help me resolve this issue, I am currently learning BASH SHELL SCRIPTING

I installed python packages on Ubuntu Trusty using pip and was able to call the installed packages as expected, but on Ubuntu Xenial (installed in a virtual machine) I did the same thing using pip but could not use or see these packages until I installed these same packages via apt-get util.

Now my question are:

1. Does my running Xenial on a virtual machine change how pip works?
2. Or is there a change in Xenial on how pip works that I am should be aware of?
3. I was able to install packages on Trusty based on python2 or python3 and was to install using pip or pip3, so how would this work when I use apt-get to install or can I include version number when installing via apt-get.

I am trying build from source workbench 6.3 on Ubuntu 16.0.4, and can't seem to figure out how to start as I don't see the usual configure files, so the command ./configure doesn't work.

Here is the issue, I encrypted my installation so at boot I need to enter a passphrase. Now I want to remove this so I can resize the main drive, i have tried every possible scenario nothing works.

When I run "ecryptfs-setup-private -undo" I get "The program 'ecryptfs-> > setup-private' is currently not installed. You can install it by typing: sudo apt-get install ecryptfs-utils".

If this is the case then what is encrypting my drive. A newbie to Ubuntu so be gentle.

I simple want to achieve two things

1. Completely remove the system wide encryption, and or
2. Leave the encryption in place and re-size my boot drive by shrinking the home drive.

The explanation here is too assuming and hence complicated for a newbie, and does not address the second option.

I had to install Sphinx on Ubuntu for use with python (django) and I came across this two commands: pip install Sphinx, and then I saw this too python -m pip install Sphinx.

Are there any difference as to where Sphinx will be installed as I want to be able to use Sphinx globally ?

I get this error warning when I select to copy project files from source folder to another location (my apache root: /var/www/html/) "The directory must be accessible via your web server at URL http://localhost/html/PhpProject2/". This ends up giving an error on running the project. I want to be able to create netbeans projects in apache root and run them from netbeans.

On Ubuntu Trusty, which is the apache root directory for web pages?