linux – Booting Into Emergency Mode | Centos7

So last night I was working on my computer and it froze. I think it’s graphic card related, I do have an Nvidia card. So I rebooted the computer as I had no other option, but now it boots to emergency mode.

In journalctl -xb
There are some errors. Other then this I am out of my league here guys. Should all these errors be fixed?

Systemd(1): failed to apply kernel variables

Sudo(17755) pam_systemd(sudo:session): failed to connect to system bus: no such file or directory found.

kernel: EXT4-fs (md0): can’t find ext file system.

Failed to mount /data01

Edac abridge: cpu srcid #0, ha #0 has dimms, but ecc is disabled.

Edac: couldn’t find mci handler

Edac: failed to register device with error -19

Systemd-udevd(1422): failed to execute ‘/usr/lib/snapd/snap-device-helper’ ‘/usr/lib/snapd/snap-device-helper add snap_pulseaudio_pulseaudio /devices/pci0000:00

KVM disabled by bio

linux – What’s the boot folder in ESP?

My partition table

First disk is for data, second for OS, in the last partition Ubuntu is installed. I had now completely shifted my whole workflow from windows 10 to ubuntu. And I was thinking to give ubuntu more space or in other words, remove my unactivated windows 10. And yes, my EFI partition’s size was also small, so I wanna create a bigger one.

EFI System Partition

In above picture, ‘Microsoft’ and ‘Ubuntu’ dirs are respectively for windows 10 and ubuntu, but what about boot directory, what’s in it ? What’s its purpose ? Is the UEFI firmware installed in it ? That is what stopped me from fully formating my SSD and installing ubuntu in it.

Any further guidance will be appreciated. Thank you.

linux – Finding a solution to a Network programming issue

I have a question how can i implement such a solution for this problem : there is a program which it must be run in a shell, as for example:
./desiredprogram ifs=eth01,eth02,eth03

1 – i want to bridge the interfaces as the program inputs together , the entered interfaces as input parameters must be bridged together by program, and it must be listen in passive mode 2 – i want it to hold the statistics of packets (in Network and Transport Layers) how can i implement this ? and could you please tel me which books and topics would be helpful for my question ? Thanks in advcance

linux – Making service listen on pptpd localip in Ubuntu Server

I put the following two lines in /etc/pptpd.conf:


Then I type service pptpd restart.

As a simple test, in one terminal, I type netcat -l 1111 and in another terminal, I type netcat 1111. However the second terminal returns

(UNKNOWN) ( 1111 (?) : Connection refused

How can I make this work?

Fresh linux install changing boot priority for reasons I can’t understand

Recently installed Manjaro KDE on a new SSD with no problems. Windows 10 on a separate HDD. When installing I was prompted what drive to launch the boot-loader, I selected the SSD. No problems. On launch I’d get a GRUB screen giving me the option to boot Manjaro or Windows 10. Today I reinstalled linux after some tinkering following the exact same process, this time no option regarding the boot-loader. Now when I boot my PC I have no GRUB screen. My Windows 10 drive doesn’t even appear in boot priority in the BIOS. Only way to launch is to enter the boot menu through the BIOS and select the drive. I’m just curious about what’s going on here and why?

linux – How safe is dm-crypt/LUKS? Would TPM make me more secure in this case?

I’ve been looking to purchase a new laptop and I need to have security in mind. I’ve specifically been looking for laptops with discrete or integrated TPM because it’s been my understanding that TPM would improve disk encryption security, but after doing some more research I’ve heard a lot of sources saying that it doesn’t really make a difference and some go so far as to suggest TPM has unpatched vulnerabilities and may even be backdoored by intelligence agencies such as the NSA.

For someone such as myself who is becoming more active in activism and investigative journalism, should I bother with TPM? And how safe is dm-crypt/LUKS? I currently use Linux Mint which I believe uses LUKS by default for disk encryption and I’m wondering how vulnerable it is to attackers with physical access to my laptop.

(P.S I’ve heard of Qubes but at the moment I’m unable to use it. In my case I’ll be using Linux Mint + AppArmor and sometimes Whonix when appropriate.)

SSH between two servers Linux and AIX

I am trying to do passwordless SSH between two server Linux (source) and AIX (destination)

For this i have created public key in Linux server and coped this public key in destination server user profile (in path .ssh/authorized_keys).Also this file is given proper permission.

In /etc/ssh/sshd_config i have uncommented below

PubkeyAuthentication yes
AuthorizedKeysFile        .ssh/authorized_keys

But when i am trying to to SSH from Linux to AIX i am getting below error

ssh user@AIX-server ls -a
Permission denied, please try again
Permission denied, please try again
Permission denied (publickey,password,keyboard-interactive,hostbased)

centos7 – Change linux shell

On my Centos7 Server I have different shells for my users.

For example the terminal as root looks like:

(root@hostname www)#.

The terminal as a different user looks like bash-4.2$.

If I type echo $0 to get the currently used shell I get /bin/bash on my different user and -bash on my root.

Do I have to configure the shell for my different user to make it looks like the shell for my root?

Is there a way to use the shell used in Debian (bash) to see the full path of my location? (root@server:/var/www# instead of root@server www).

Thanks for your help.

networking – why linux host do not contain ip after add bridge network with kvm virtual machine

After I join the bridge network br0 in my Fedora 32 workstation machine, my host machine config look like this using ifconfig:

(dolphin@MiWiFi-R4CM-srv .ssh)$ ifconfig
br0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet  netmask  broadcast
        inet6 fe80::4b2:78ff:fe35:2c73  prefixlen 64  scopeid 0x20<link>
        ether 06:b2:78:35:2c:73  txqueuelen 1000  (Ethernet)
        RX packets 262706  bytes 549324981 (523.8 MiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 176370  bytes 17361895 (16.5 MiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

eno2: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        ether 2c:f0:5d:2c:6e:d5  txqueuelen 1000  (Ethernet)
        RX packets 930979  bytes 1290671619 (1.2 GiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 352599  bytes 31255959 (29.8 MiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
        device interrupt 16  memory 0xa1200000-a1220000  

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet  netmask
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        loop  txqueuelen 1000  (Local Loopback)
        RX packets 8324  bytes 3833687 (3.6 MiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 8324  bytes 3833687 (3.6 MiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

virbr0: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
        inet  netmask  broadcast
        ether 52:54:00:39:c6:9f  txqueuelen 1000  (Ethernet)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 0  bytes 0 (0.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

vnet0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet6 fe80::fc54:ff:fe36:a8ef  prefixlen 64  scopeid 0x20<link>
        ether fe:54:00:36:a8:ef  txqueuelen 1000  (Ethernet)
        RX packets 178749  bytes 13514111 (12.8 MiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 334263  bytes 712473913 (679.4 MiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

vnet1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet6 fe80::fc54:ff:fe90:27a6  prefixlen 64  scopeid 0x20<link>
        ether fe:54:00:90:27:a6  txqueuelen 1000  (Ethernet)
        RX packets 479  bytes 49167 (48.0 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 29585  bytes 2427883 (2.3 MiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

vnet2: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet6 fe80::fc54:ff:fe1b:74f9  prefixlen 64  scopeid 0x20<link>
        ether fe:54:00:1b:74:f9  txqueuelen 1000  (Ethernet)
        RX packets 559  bytes 61180 (59.7 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 29231  bytes 2402385 (2.2 MiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

althrough everything going fine, I could using internet and kvm virtual machine could ping host machine and host machine could login kvm virtual machine.But I still have confusing qustion:why my host interface eno2 ip disappeared? what is my host ip?