D.Zou's questions

I have ubuntu 20 server installed and during the installation it asked me if I want to use LVM and I did. Now I am trying to mount the LVM but I am getting confused on what to do.

$ sudo lvmdiskscan
  /dev/loop0 [      69.88 MiB] 
  /dev/loop1 [      55.38 MiB] 
  /dev/loop2 [     <31.09 MiB] 
  /dev/sda2  [       1.00 GiB] 
  /dev/loop3 [      55.46 MiB] 
  /dev/sda3  [      <1.64 TiB] LVM physical volume
  0 disks
  5 partitions
  0 LVM physical volume whole disks
  1 LVM physical volume
$ df -h
Filesystem                         Size  Used Avail Use% Mounted on
udev                               7.8G     0  7.8G   0% /dev
tmpfs                              1.6G  1.7M  1.6G   1% /run
/dev/mapper/ubuntu--vg-ubuntu--lv  196G  6.2G  180G   4% /
tmpfs                              7.9G     0  7.9G   0% /dev/shm
tmpfs                              5.0M     0  5.0M   0% /run/lock
tmpfs                              7.9G     0  7.9G   0% /sys/fs/cgroup
/dev/sda2                          976M  104M  806M  12% /boot
/dev/loop0                          70M   70M     0 100% /snap/lxd/19188
/dev/loop2                          32M   32M     0 100% /snap/snapd/10707
/dev/loop1                          56M   56M     0 100% /snap/core18/1944
/dev/loop3                          56M   56M     0 100% /snap/core18/1988
tmpfs                              1.6G     0  1.6G   0% /run/user/1000
$ sudo pvscan
  PV /dev/sda3   VG ubuntu-vg       lvm2 [<1.64 TiB / 1.44 TiB free]
  Total: 1 [<1.64 TiB] / in use: 1 [<1.64 TiB] / in no VG: 0 [0   ]
$ sudo vgscan
  Found volume group "ubuntu-vg" using metadata type lvm2
$ sudo vgchange -ay 
  1 logical volume(s) in volume group "ubuntu-vg" now active
$ sudo lvscan 
  ACTIVE            '/dev/ubuntu-vg/ubuntu-lv' [200.00 GiB] inherit
$ sudo vgdisplay
  --- Volume group ---
  VG Name               ubuntu-vg
  System ID             
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  2
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                1
  Open LV               1
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               <1.64 TiB
  PE Size               4.00 MiB
  Total PE              428848
  Alloc PE / Size       51200 / 200.00 GiB
  Free  PE / Size       377648 / 1.44 TiB
  VG UUID               Qy1h42-pePJ-6P8L-kNjM-5bN4-kg88-oWL8lA
  

So as you can see I have /dev/sda3 physical volume. It is part of ubuntu-vg volume group. But when I look at the vgdisplay, I see the free PE of 1.44T. So I can make a new VG that uses those free space right?

My end goal is just to mount that extra space and using it as a movie storage device and mount it on /mnt/media and I am not sure how to proceed from there.

edit:

$ sudo lsblk
NAME                      MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
loop0                       7:0    0 69.9M  1 loop /snap/lxd/19188
loop1                       7:1    0 55.4M  1 loop /snap/core18/1944
loop2                       7:2    0 31.1M  1 loop /snap/snapd/10707
loop3                       7:3    0 55.5M  1 loop /snap/core18/1988
sda                         8:0    0  1.7T  0 disk 
├─sda1                      8:1    0    1M  0 part 
├─sda2                      8:2    0    1G  0 part /boot
└─sda3                      8:3    0  1.7T  0 part 
  └─ubuntu--vg-ubuntu--lv 253:0    0  200G  0 lvm  /mnt/media
sr0                        11:0    1 1024M  0 rom  

I am trying out the Jetson Nano (think an Ubuntu 18 for AI stuff) and I am running into this issue.

As you can see from screenshot, I got both an SSH session and a noMachine remote desktop into the box.

In the above picture, when I run: camera detection and have to execute this command:

./detectnet /dev/video0 # V4L2 camera

via the remote desktop it works.
If I do it via the ssh terminal it fails.

Like here: The error is at OpenGL trying to create the display, which makes sense. It is trying to do it over an SSH session.

bounding box 1  (325.916412, 19.095182)  (1243.184204, 700.690735) 
w=917.267822  h=681.595581 [OpenGL] glDisplay -- set the window size
to 1280x720 [OpenGL] creating 1280x720 texture (GL_RGB8 format,
2764800 bytes) Segmentation fault (core dumped)

My question is, when I run the command over SSH, how do I force the output to be displayed on the NoMachine desktop?

Or rephrased another way, I want to execute the commands over ssh but have the video results displayed on the remote desktop.

added picture of what if I use: export DISPLAY=":0.0"

$ cat /etc/fstab

gUID=b8e93e66-9575-44f9-8ef5-97665713b7e3 / ext4 defaults 0 0
/swap.img       none    swap    sw      0       0
//192.168.1.103/share /mnt/Media cifs username=guest,uid=1000 g g

Hi all

I am trying to mount a Buffalo Linkstation on my Ubuntu 18.04 VM.
The above is my /etc/fstab, but whenever I run sudo mount -a I get parse error at line 4 -- ignored. I followed the instruction on this webpage: https://mginternet.wordpress.com/2012/01/05/mounting-a-buffalo-linkstation-share-on-ubuntu/

and it seemed pretty correct. The linkstation does have the share folder and I can access it on windows just fine.

The IP address is reachable from my VM as well via ping.

I am at a loss as to what could have caused this.

I created two LVM partitions, and can mount/use them. But when I try to mount it with UUID I get a message that says it can't find the UUID.

sudo lvdisplay
--- Logical volume ---
LV Path                /dev/vg00/VolProject
LV Name                VolProject
VG Name                vg00
LV UUID                HUhRED-ZUwG-cutq-fniL-1OOE-cZrd-ofoDZ3
LV Write Access        read/write
LV Creation host, time ubuntu, 2017-04-04 18:41:55 -0700
LV Status              available
# open                 1
LV Size                17.00 GiB
Current LE             4351
Segments               3
Allocation             inherit
Read ahead sectors     auto
- currently set to     256
Block device           252:0

--- Logical volume ---
LV Path                /dev/vg00/volBackup
LV Name                volBackup
VG Name                vg00
LV UUID                KZ6Y65-L9Qo-ShIz-pQ88-nIyD-P1n5-RGWcrw
LV Write Access        read/write
LV Creation host, time ubuntu, 2017-04-04 18:42:42 -0700
LV Status              available
# open                 0
LV Size                6.99 GiB
Current LE             1790
Segments               2
Allocation             inherit
Read ahead sectors     auto
- currently set to     256
Block device           252:1

ubuntu:/dev/vg00$ cat /etc/fstab
UUID=56b92ca1-312c-45e6-8f57-8c80762f96b9 / ext4 errors=remount-ro 0       1
UUID=07d0cb84-79a6-47bd-a155-cbfd045cf6ca none swap sw             0       0
/dev/fd0        /media/floppy0  auto    rw,user,noauto,exec,utf8   0       0
#/dev/vg00/VolProject /home/davy/mnt auto defaults 0 0
UUID=HUhRED-ZUwG-cutq-fniL-1OOE-cZrd-ofoDZ3 /home/davy/mnt auto defaults 0 0
ubuntu:/dev/vg00$ blkid /dev/vg00/VolProject
ubuntu:/dev/vg00$ blkid /dev/vg00/volBackup

and when I do the mount -a:

ubuntu:/dev/vg00$ sudo mount -a
mount: can't find UUID=HUhRED-ZUwG-cutq-fniL-1OOE-cZrd-ofoDZ3

why is this happening? If I used the mount via /dev/vg00/VolProject it works, but if I use it's UUID it says that it can't find it. VG is created per instructions here: http://www.tecmint.com/manage-and-create-lvm-parition-using-vgcreate-lvcreate-and-lvextend/

Ubuntu comes with several different variants of the kernel. I am talking about the different kernel version that you can select at boot time.

Say I am on kernel 4.4.1, and I installed the package nfs-common. Then I switch to kernel 4.4.2. Should the nfs-common still be there? I guess it shouldn't right?

I have an HP envy 15 inch, newly installed with U16 it has RT3290 wifi chip.

My laptop has an wifi switch that I haven't been able to turn on. It always shows an orange light which indicates the wifi is off. I suspect this is what is causing me a whole host of wifi related issues.

I ran rfkill but it listed nothing. So how can I make the physical wifi switch work?

Edit for more info as per request:

root@HP-ENVY# rfkill list all
root@HP-ENVY# lsmod | grep -e wmi -e lap
hp_wmi                 16384  0
sparse_keymap          16384  1 hp_wmi
snd_rawmidi            32768  1 snd_seq_midi
snd_seq_device         16384  3 snd_seq,snd_rawmidi,snd_seq_midi
snd                    81920  17 snd_hwdep,snd_timer,snd_hda_codec_hdmi,snd_hda_codec_idt,snd_pcm,snd_seq,snd_rawmidi,snd_hda_codec_generic,snd_hda_codec,snd_hda_intel,snd_seq_device
wmi                    20480  1 hp_wmi
root@HP-ENVY# 

I have an HP Envy 15 with the RT3290 from ralink. It had Win8 on it which I have completely removed and installed ubuntu 16.04 on it.

I have been trying to get the wireless to work and haven't been able to.

I have followed these two guides here:

How do I get a Ralink RT3290 wireless card working?

How do I get an RT3290 wireless card to work?

and have compiled the source, generated the module and it is installed. I also added the module in /etc/module file so it will launch at boot. lsmod shows it there:

:/usr/src$ lsmod | grep rt
rt3290sta            1155072  0

:/usr/src$ lspci
08:00.0 Network controller: Ralink corp. RT3290 Wireless 802.11n 1T/1R PCIe
08:00.1 Bluetooth: Ralink corp. RT3290 Bluetooth
..with -n 
08:00.0 0280: 1814:3290
08:00.1 0d11: 1814:3298

but ifconfig still shows this:

rename6   Link encap:Ethernet  HWaddr 00:00:00:00:00:00  
          BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)
          Interrupt:17 

:/usr/src$ ifup rename6
Unknown interface rename6

:~/Downloads/RT3290_Linux_v2600$ iwpriv 
virbr0-nic  no private ioctls.

rename6   Available private ioctls :
          set              (8BE2) : set 1024 char  & get   0      
          connStatus       (0004) : set 1024 char  & get 2047 char 
          driverVer        (0005) : set 1024 char  & get 2047 char 
          bainfo           (0006) : set 1024 char  & get 2047 char 
          descinfo         (0007) : set 1024 char  & get 2047 char 
          radio_off        (000A) : set 1024 char  & get 2047 char 
          radio_on         (000B) : set 1024 char  & get 2047 char 
          show             (0015) : set 1024 char  & get 2047 char 
          adhocEntry       (0016) : set 1024 char  & get 2047 char 
          bbp              (8BE3) : set 2047 char  & get 2047 char 
          mac              (8BE5) : set 1024 char  & get 1024 char 
          rf               (8BF3) : set 2047 char  & get 2047 char 
          e2p              (8BE7) : set 1024 char  & get 1024 char 
          stat             (8BE9) : set   0       & get 2047 char 
          get_site_survey  (8BED) : set   0       & get 1024 char 

virbr0    no private ioctls.

eno1      no private ioctls.

lo        no private ioctls.

lspci -v output:

08:00.0 Network controller: Ralink corp. RT3290 Wireless 802.11n 1T/1R PCIe
    DeviceName: Ralink RT3290LE 802.11bgn 1x1 Wi-Fi and Bluetooth 4.0 Combo Ada
    Subsystem: Hewlett-Packard Company Ralink RT3290LE 802.11bgn 1x1 Wi-Fi and Bluetooth 4.0 Combo Adapter
    Flags: bus master, fast devsel, latency 0, IRQ 17
    Memory at 61510000 (32-bit, non-prefetchable) [size=64K]
    Capabilities: <access denied>
    Kernel driver in use: rt2860
    Kernel modules: rt2800pci, rt3290sta

The above lspci -v would seem to show that I have two kernel modules for this device, so I ran modprobe to remove rt2800pci and did lsmod to confirm it is gone. but when I ran lspci -v again it still shows.

I also searched for the kernel and rt3290sta.ko is present:

:/lib/modules/4.4.0-22-generic/kernel/drivers/net/wireless$ ls
adm8211.ko       ath           b43        hostap    libertas           mwifiex   ray_cs.ko      rt2x00        zd1201.ko
airo_cs.ko       atmel_cs.ko   b43legacy  ipw2x00   libertas_tf        mwl8k.ko  realtek        rt3290sta.ko

davy@davy-envy:/lib/modules/4.4.0-22-generic/kernel/drivers/net/wireless/rt2x00$ cat /etc/modprobe.d/blacklist-ralink.conf 

#Wireless drivers conflicting with rt3290sta
blacklist rt2800pci
blacklist rt2x00pci  
blacklist rt2860

I tried rebooting, and to search in /var/log/messages and dmesg, both files are empty, not messages. So I greped the whole /var/log folder for anything rt3290 but I got nothing.

So now I am out of ideas.

I am playing around with swap and added my own swap partition. but when I do I noticed something odd.

test@ubuntu:~/5Gdisk$ cat /proc/swaps
Filename   Type            Size    Used    Priority
/dev/sda5  partition       4192252 0       -1
/dev/sdb2  partition       5242876 0       -2

and my /etc/fstab

UUID=<bla bla> none  swap sw 0 0
/dev/sdb2      swap  swap sw 0 0

sdb2 is the swap partition that I added. I also checked the man page of swapon, and it says for priority it should be from -1 to 32767. So why does my swap parition has a priority of -2?

This is ubuntu 15. Thanks

I am learning about ulimit right now and this is a bit confusing.

I start with this as my default ulimit.

test@ubuntu:~$ ulimit -n
1024

I can see my hard and soft limit:

test@ubuntu:~$ ulimit -Sn
1024
test@ubuntu:~$ ulimit -Hn
65536

If I do the below I set the ulimit to my hard limit.

test@ubuntu:~$ ulimit -n hard
test@ubuntu:~$ ulimit -n
65536

But if I try to change it to my soft limit it doesn't work. It is still hard.

test@ubuntu:~$ ulimit -n soft
test@ubuntu:~$ ulimit -n
65536

I have two questions:

1. Why can't I lower it back to the soft limit.

2. What is the difference between these two below? One shows me unlimited the other shows 1024. (I started a new shell to be sure.)

   test@ubuntu:~$ ulimit
   unlimited
   test@ubuntu:~$ ulimit -n 1024

Running Ubuntu15 Desktop edition with the default bash environment.

Thanks

This is just a bad idea that I just had.

Is there a way create users accounts on the fly?

Say I have a Ubuntu vm created, and I want to give a bunch of people access. But for whatever reason I don't particularly care about what they do with it.

How can I set it up that when user A ssh into the vm the user's account will automatically be created?

and yes, I know in theory, I could just create a guest account and share that with the people that need access. but then a bunch of people will be sharing the account and I also want to log what everybody did so having them on the same account would make it very difficult.

and yes, this is a very bad idea.

I got a Ubuntu 15 VM and I am adding a second virtual disk for the home partition.

I moved the old home to home.old. and have mounted the new home on the new disk. and the mount is successful. But when I go see home, I don't see the directory for my test user. the directory for test is still under home.old.

I also tried to create a new test user, test2 but neither home nor home.old shows me the directory test2.

test2@test-virtual-machine:/$ cd /home
test2@test-virtual-machine:/home$ ls
lost+found
test2@test-virtual-machine:/home$ cd ..
test2@test-virtual-machine:/$ ls /home.old/
test
test2@test-virtual-machine:/$

What's going on here?

Thanks

EDIT: as per request

test@test-virtual-machine:/home$ cd ~
bash: cd: /home/test: No such file or directory
test@test-virtual-machine:/home$ pwd
/home
test@test-virtual-machine:/home$ ls
aquota.user  lost+found
test@test-virtual-machine:/home$

I am exploring the autofs with ubuntu, and I got it working, but something doesn't quite make sense to me.

this is what I got:

$ pwd
/nfs/nfs/mnt/nfs_export
$ ls
kvm_the_1st.img  lost+found  success

as you can see it mounts successfully. My problem is the number of folders that exists as the path to get to my stuff.

My auto.master:

/nfs    /etc/auto.nfs

My auto.nfs:

nfs            -fstype=nfs4            nfs:/

on the NFS server I have the following for export:

/mnt/nfs_export *(rw,sync,no_root_squash,no_subtree_check)

I am guessing it is because my auto.master specifies /nfs, then my auto.nfs has another nfs, then the root directory that gets exported from the NFS right? But shouldn't it only export the nfs_export?

I had wanted to set it up so the /nfs would go directly to the export_nfs folder on the nfs server. Meaning if I cd into /nfs I should see files such as "success".

and a follow up question: I know via manual nfs via /etc/fstab I can change things such as rsize and wsize, but with autofs where/how would I make that change?

I am playing with KVM migration, and I got an error about unsafe migration due to hdd cache settings. I found the fix, which is to set the cache to none and it works after I made the change.

But that leads me to wonder the following:

1. what effect, performance wise, will this have on my kvm?
2. why can't i migrate with hdd cache?

Thanks

I am playing with my ubuntu VM (vmware), and I just got this message pop up in my conosle, what does it mean?

I have a ubuntu 14.10, and am trying to telnet into it via port 5060 but I keep failing. I always get the message "Connection closed by foreign host".

I checked my iptable, it is default policy to ACCEPT, and ufw is inactive.

So I should be able to telnet into 5060 right? What else could be blocking it?

root@server:/var/log# iptables --list
Chain INPUT (policy ACCEPT)
target     prot opt source               destination         

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination         

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination         
root@server:/var/log# 

root@server:/var/log# ufw status
Status: inactive
root@server:/var/log# 

but telneting just gives me this.

user@host ~
$ telnet 192.168.0.5 5060
Trying 192.168.0.5...
Connected to 192.168.0.5.
Escape character is '^]'.
Connection closed by foreign host.

I want to run sip traffic on that port later but I can't even open the port right now.

Thanks guys

I have recently been made a temporary owner of an old 12.10 Ubuntu machine so I can upgrade it to the latest(14.04). So I am trying to upgrade to the 13.04 as per ubuntu website, and from there to 14.04, but I seemed to have run into the apt-get bug:

root@camolls1000774583:/etc/apt# do-release-upgrade 
Checking for a new Ubuntu release
Your Ubuntu release is not supported anymore.
For upgrade information, please visit:
http://www.ubuntu.com/releaseendoflife

Traceback (most recent call last):
File "/usr/bin/do-release-upgrade", line 145, in <module>
fetcher.run_options += ["--mode=%s" % options.mode,
AttributeError: type object 'DistUpgradeFetcherCore' has no attribute 'run_options'

I googled around, apparently the fix was pushed in a upgrade and was placed in quantal repo.

But when I tried to run apt-get update and apt-get upgrade all my quantal repos came back as 404 not found or ignored. I am guessing since Quantal is EOL they took away the repo.

So how do I upgrade to Raring without quantal repo?

I have also attached a copy of my sources.list in case that helps. I can't nuke it. I need the user's data intact.

thanks

Edited for additional clarification.

I recently installed Ubuntu Server edition 13.10 (Saucy Salamander). But I have run into a bit of problem.

At the end of the installation, it asks about several extra packages whether you want them or not, like OpenSSH server and virtual machine host. Here's what I'm looking at:

Now, my problem is that I can't remember if I have checked the "virtual machine host" checkbox. How do I check if my server has the corresponding packages?

What packages come with the virtual machine host?