Install issues over serial?

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bdowne01
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Install issues over serial?

Post by bdowne01 » 2014/10/21 15:04:24

Hello,

Wondering if anyone has successfully done an PXEboot install with CentOS7 purely over a serial console? We use SOL (Supermicro Serial over Lan, specifically) on headless servers, and have been doing Kickstart installs with SOL redirection from Anaconda since CentOS4. However, for some reason Anaconda never fires on the CentOS7 install. Instead, Systemd seems to hang very early in the initialization process. If we remove the "console=" directive from the kernel APPEND line, the install and kickstart work perfectly (monitored via KVM).

Here's the PXE boot entry:

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LABEL CentOS 7
   MENU LABEL CentOS 7
   KERNEL images/centos/x86_64/7.0/vmlinuz
   APPEND initrd=images/centos/x86_64/7.0/initrd.img nomodeset inst.text inst.headless console=ttyS2,19200n8 inst.ks=ftp://172.24.0.97/ks/centos7.ks  
With this PXE configuration, the installation process never even gets to the point of downloading the kickstart (monitoring FTP logs) and instead seems to stop output here via SOL:

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[   14.906468] Freeing unused kernel memory: 1584k freed
[   14.939923] systemd[1]: systemd 208 running in system mode. (+PAM +LIBWRAP +AUDIT +SELINUX +IMA +SYSVINIT +LIBCRYPTSETUP +GCRYPT +ACL +XZ)
[   15.014810] systemd[1]: Running in initial RAM disk.
[   45.067516] systemd[1]: No hostname configured.
[   45.094825] systemd[1]: Set hostname to <localhost>.
[   45.124873] systemd[1]: Initializing machine ID from random generator.
[   45.184707] systemd[1]: Starting -.slice.
I believe Plymouth seems to be using some sort of VGA mode for the install--regardless of the "inst.text" and "inst.headless" directives. At boot, output still alludes to a graphic mode:

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[    0.000000] Console: colour VGA+ 80x25
[    0.000000] console [ttyS2] enabled
I think what's happening is the initialization is dying because the SOL redirect cannot handle the "VGA+ 80x25" mode. It need to be pure, old-school text. If I modify the PXE APPEND line to redirect to both ttyS2 and tty0 as follows:

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LABEL CentOS 7
   MENU LABEL CentOS 7
   KERNEL images/centos/x86_64/7.0/vmlinuz
   APPEND initrd=images/centos/x86_64/7.0/initrd.img nomodeset inst.text inst.headless console=ttyS2,19200n8 console=tty0 inst.ks=ftp://172.24.0.97/ks/centos7.ks
Then attach a KVM, I see the initialization process proceed a but further (it downloads the kickstart and starts pulling OS files from the mirror server), but still hangs here:

Image

A very frustrating exercise in patience, to say the least :)

Thanks for any help.

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