What is sr0 linux

What is Dev sr0 in Linux?

/dev/sr0. is the first SCSI CD-ROM device in the system. This may be misleading as SCSI and SATA are interchangeable in Linux terminology. There is also SCSI emulation of ATAPI devices in some Unix systems (in FreeBSD it’s called ATAPICAM) which makes ATAPI CD-ROM devices appear to be SCSI.

What is Dev sg0?

And what was failing. /dev/sg0 is a generics SCSI device, the one used by burning software to access the writing capabilities of your CD burner drive, using the ide-scsi layer driver. / dev/scd0 is the SCSI device used for CD-ROM accessing.

How do I mount a DVD in Linux?

To mount the CD or DVD on Linux operating systems:

1. Insert the CD or DVD in the drive and enter the following command: mount -t iso9660 -o ro /dev/cdrom /cdrom. where /cdrom represents the mount point of the CD or DVD.
2. Log out.

How do I know if my CD is mounted Linux?

Usually on Linux, when an optical disc is mounted, the eject button is disabled. To determine whether anything is mounted in the optical drive, you can check the contents of /etc/mtab and look for either the mount point (e. g. /mnt/cdrom ) or the device for the optical drive (e. g. /dev/cdrom ).

How do I open a DVD on Linux?

(Alternatively, you can run sudo apt-get install vlc to install it from the command line.) Once installed, insert your DVD and launch VLC. Click the “Media” menu in VLC, select “Open Disc,” and select the “DVD” option. VLC should automatically find a DVD disc you’ve inserted and play it back.

What is SG device Linux?

The Linux sg driver is a upper level SCSI subsystem device driver that is used primarily to handle devices _not_ covered by the other upper level drivers: sd (disks), st (tapes) and sr (CDROMs and DVDs). The sg driver is used for enclosure management, cd writers, applications that read cd audio digitally and scanners.

How do I find my device name in Linux?

The procedure to find the computer name on Linux:

1. Open a command-line terminal app (select Applications > Accessories > Terminal), and then type:
2. hostname. hostnamectl. cat /proc/sys/kernel/hostname.
3. Press [Enter] key.

How do I mount an ISO in Linux?

How to Mount ISO File on Linux

1. Create the mount point directory on Linux: sudo mkdir /mnt/iso.
2. Mount the ISO file on Linux: sudo mount -o loop /path/to/my-iso-image.iso /mnt/iso.
3. Verify it, run: mount OR df -H OR ls -l /mnt/iso/
4. Unmount the ISO file using: sudo umount /mnt/iso/

How do I access the CD-ROM on Linux?

To mount a CD-ROM on Linux:

1. Switch user to root : $ su – root.
2. If necessary, enter a command similar to one of the following to unmount the currently mounted CD-ROM, then remove it from the drive:
3. Red Hat: # eject /mnt/cdrom.
4. UnitedLinux: # eject /media/cdrom.

How do I access CD-ROM?

Open System Information. In the System Information window, click the + symbol next to Components. If you see “CD-ROM,” click it once to display the CD-ROM in the left window. Otherwise, click “+” next to “Multimedia” and then click “CD-ROM” to see the CD-ROM information in the left window.

How mount CD in Kali Linux?

Fix the Mount CD-ROM in Kali Linux Installing Process.

1. Kali Linux – Manually Mount CD-ROM. …
2. Kali Linux – Show IDs. …
3. Kali Linux – Make CD-ROM Folder. …
4. Kali Linux – Mount the Folder. …
5. Kali Linux – Exit and Go Back To Installing Process. …
6. Testing CD-ROM.

Where is CD mounted in Ubuntu?

Usually, if a CD or DVD is inserted, you can see them under /dev/cdrom . You wont be able to view the contents from that location directly such as by doing cd /dev/cdrom or ls . That’s it. You should be able to see the files under /media folder now.

How do I check my CD drive in Ubuntu?

Once you mount a CD/DVD,you can find it in /media/DISC_NAME . Show activity on this post. If you insert a CD or DVD, it should be automatically detected and will appear as a removable media drive in the nautilus file browser, otherwise it will be hidden.

How do I run a CD in Ubuntu?

1. First step (actually optional) is to get VLC media player. You can install VLC from Ubuntu Software Center or using the following command in terminal: sudo apt-get install vlc. …
2. Once we have it, lets install libdvdread4 and libdvdnav4. Use the following command in the terminal: sudo apt-get install libdvdread4 libdvdnav4.

How do I use a CD in Ubuntu?

File & Directory Commands

1. To navigate into the root directory, use “cd /”
2. To navigate to your home directory, use “cd” or “cd

”

To navigate up one directory level, use “cd ..”

To navigate to the previous directory (or back), use “cd -“

How do I read a DVD in Ubuntu?

To open the file manager, click the filing cabinet icon on the Ubuntu Launcher. If the DVD is mounted, it appears as a DVD icon at the bottom of the Ubuntu Launcher. To open the DVD in the file manager, click the DVD icon. The DVD appears in the list on the left side of the file manager screen.

Источник

what’s the difference between /dev/hdc, /dev/sr0, /dev/cdrom

I created 2 virtual machines with VMware Workstation 7. They have identical hardwares. One guest is CentOS 5.6, another is Mandriva 2011. When I try to mount the cdrom in guest OS, in CentOS, I should execute

in Mandriva, I should execute

I also remebered in some other Linux variant, I had to use

My questions are:

1. What’s the difference between hdc, sr0 or cdrom?
2. Is there a consistent way to mount cdrom in all Linux variants?

3 Answers 3

is the third IDE hard drive — Secondary Master.

is the first SCSI CD-ROM device in the system. This may be misleading as SCSI and SATA are interchangeable in Linux terminology. There is also SCSI emulation of ATAPI devices in some Unix systems (in FreeBSD it’s called ATAPICAM) which makes ATAPI CD-ROM devices appear to be SCSI. Some older software is written purely to interface with SCSI peripherals and can’t work with ATAPI ones, so this emulation layer can be quite useful.

And yes, that is a symlink to one of the above — either done manually with ln or through the udev configuration.

/dev/hdc is a device on the ide controller.

/dev/sr0 is a device on the scsi controller.

/dev/cdrom is a symlink to either /dev/sr0 or /dev/hdc or whichever block device is appropriate. Most distributions come with a script that automatically sets up /dev/cdrom to be the correct device. So you’re generally safe using /dev/cdrom . If you don’t have /dev/cdrom you can always set it up yourself with ln -s

Источник

Buffer I/O error on dev sr0

Привет. После загрузки ОС в лог сыпется ошибка

скажи модему отрубить привод, т.е. работать в режиме сетевая карта онли (смотри команды на 4pda в теме про свой модем)

Я так свой модем пару недель назад ушатал. AT команду для возвращения в дефолт не знаю, а интернет не работает.

Модем в каком режиме всё-таки работает? Просто eject /dev/sr0 ошибку с приводом не снимает? Модем подключается непосредственно в порт USB?

При подключении как модем определяется (какое устройство видит система)? // неплохо бы модель указать

Модем МТС 320s, не помню как хуавейевский оригинал называется. Я его в режим только модем перевёл. lsusb видит его как 12d1:1506 Huawei Technologies Co., Ltd.. Но при этом он не работает. Даже в винде перестал работать через фирменную утилиту для подключения. У меня в ящике стола другой модем валялся. Я туда симку переставил и больше не экспериментировал.

Появляются два устройства /dev/ttyUSB0 и /dev/ttyUSB1.

Модем МТС 320s, не помню как хуавейевский оригинал называется. Я его в режим только модем перевёл. lsusb видит его как 12d1:1506 Huawei Technologies Co., Ltd..

Возможно в dmesg пишет модель «Huawei . » Какой командой режим переключали?

Появляются два устройства /dev/ttyUSB0 и /dev/ttyUSB1.

Я обычно видел 1 или 3 порта (впрочем это ни о чём не говорит)

Интернеты опознают модель как «Huawei E3121» и предлагают команды для изменения режима работы модема

Я бы «по-быстрому и на коленке» сделал так.

• подключил модем (вероятно, симкарта всё же необходима — подойдёт любая допустимая , не обязательно действующая)
• после появления в системе устройств /dev/ttyUSB* отключил в NetworkManager «Мобильные сети» (или ModemManager) в разных GUI может по-разному называться. Да перед этим в терминале посмотреть lsof /dev/ttyUSB0 — если напишет, что порт занят ModemManager, то скорее всего мы выбрали нужный порт. Если нет, то смотреть и другие /dev/ttyUSB* придётся
• Далее потребуется 2 терминала или 2 вкладки в терминале (от root!)
• в одном выполняем от рута cat /dev/ttyUSB0 — сюда модем будет отвечать на наши запросы
• в другом терминале от root мы будем отправлять команды модему. Команды выполняются «вручную» с последующим просмотром ответов

Возможно это вариация вот этой проблемы: systemd-udevd грузит процессор (я там хотел поотлаживать это, но автор темы куда-то пропал).

Запусти udevadm monitor и посмотри что он выводит.

Источник

Linux /dev directory questions (what is /dev/sr0?)

loosus

Banned

Linux newb here. (Yeah, here comes trouble.)

What is sr0 under the /dev directory?

Here’s why I ask: I was mounting the CD-ROM, and I know that I can use /dev/cdrom, but I did an ls -l just to see what /dev/cdrom is, and it’s actually a link file that points to the underlying /dev/sr0.

So, is sr0 the actual CD-ROM drive? Or something else? And why is it that when I look at Linux documentation, the CD-ROM drive is usually referred to as hda or something similar?

Anybody who can provide some guidance would be greatly appreciated. Some good, newb-friendly documentation on this would be even better.

Please help me with my bad english

It should be your CD/DVD device.

-Reread your post, hda are always and only hard drive partition, unless you mount something else in a hda directory.

Cheeto

Member

PetriP-TNT

Member

/dev/sr0 should be your cd-drive

Harddrives are usually referred as hda:s, but the latest ubuntu at least changed them to sda:s and external drives from sda:s to sdb:s

loosus

Banned

Okay, that makes sense. Do the letters in «sr» stand for anything?

Also, I don’t really understand the numbering scheme. what is the difference between hda and hda1? Also, when does hdb come into effect? I’ve seen different documentation refer to these devices, and I’m just trying to make sense of them.

Also, is there any way to make sense of my mount dump and what the lines mean?

[root@localhost dev]# mount
/dev/mapper/VolGroup00-LogVol00 on / type ext3 (rw)
proc on /proc type proc (rw)
sysfs on /sys type sysfs (rw)
devpts on /dev/pts type devpts (rw,gid=5,mode=620)
/dev/sda1 on /boot type ext3 (rw)
tmpfs on /dev/shm type tmpfs (rw)
none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)
sunrpc on /var/lib/nfs/rpc_pipefs type rpc_pipefs (rw)
fusectl on /sys/fs/fuse/connections type fusectl (rw)
gvfs-fuse-daemon on /root/.gvfs type fuse.gvfs-fuse-daemon (rw,nosuid,nodev)
/dev/sr0 on /media/VBOXADDITIONS_2.0.4_38405 type iso9660 (ro,nosuid,nodev,uhelper=hal,uid=0)

For example, I have no idea what mapper is or what VolGroup00-LogVol00 is.

One last dumb question: I know in Linux there is basically just one huge directory structure and that other filesystems have to be mounted to it. Is there anything that determines to what device root (/) itself is mounted?

Источник

3. PCI Express I/O Virtualization Howto¶

В© 2009 Intel Corporation

3.1. Overview¶

3.1.1. What is SR-IOV¶

Single Root I/O Virtualization (SR-IOV) is a PCI Express Extended capability which makes one physical device appear as multiple virtual devices. The physical device is referred to as Physical Function (PF) while the virtual devices are referred to as Virtual Functions (VF). Allocation of the VF can be dynamically controlled by the PF via registers encapsulated in the capability. By default, this feature is not enabled and the PF behaves as traditional PCIe device. Once it’s turned on, each VF’s PCI configuration space can be accessed by its own Bus, Device and Function Number (Routing ID). And each VF also has PCI Memory Space, which is used to map its register set. VF device driver operates on the register set so it can be functional and appear as a real existing PCI device.

3.2. User Guide¶

3.2.1. How can I enable SR-IOV capability¶

Multiple methods are available for SR-IOV enablement. In the first method, the device driver (PF driver) will control the enabling and disabling of the capability via API provided by SR-IOV core. If the hardware has SR-IOV capability, loading its PF driver would enable it and all VFs associated with the PF. Some PF drivers require a module parameter to be set to determine the number of VFs to enable. In the second method, a write to the sysfs file sriov_numvfs will enable and disable the VFs associated with a PCIe PF. This method enables per-PF, VF enable/disable values versus the first method, which applies to all PFs of the same device. Additionally, the PCI SRIOV core support ensures that enable/disable operations are valid to reduce duplication in multiple drivers for the same checks, e.g., check numvfs == 0 if enabling VFs, ensure numvfs 3.2.2. How can I use the Virtual Functions¶

The VF is treated as hot-plugged PCI devices in the kernel, so they should be able to work in the same way as real PCI devices. The VF requires device driver that is same as a normal PCI device’s.

Источник