How do I drop to shell from rescue CD???
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From: Robert Nichols on 19 May 2010 10:07 On 05/18/2010 09:58 PM, Ohhhh maaan wrote: > I have a kernel panic and need to fix a typo. I don't have the install > disks, and I just want to use the CD to access the shell prompt so I > can run the commands need. I can't get to the grub boot loader screen. > > Anyway, I run this and it asks for linux or linux text, and no matter > what I do, I can't just have it load the kernel image from the rescue > CD and drop into shell. It always wants to install and asks for the > images. How in the world can someone just drop into a shell prompt? > > I've used Linux years ago and I think I recall you could just type linux > single or linux emergency at the boot CD, but nothing works with this > new CentOS 5.x rescue CD. I'm stuck at "boot:" and nothing I try just > drops/boots me into a shell prompt. Please, help! :) Once you get to the installer GUI, there should be a shell available on one of the other VTs. Try ctrl-alt-F2. -- Bob Nichols AT comcast.net I am "RNichols42"
From: Bill Waddington on 19 May 2010 11:23 On Tue, 18 May 2010 23:39:54 -0700, Ohhhh maaan <nobodyhere(a)example.com> wrote: >Keith Keller wrote: > >> ["Followup-To:" header set to comp.os.linux.misc.] >> >> On 2010-05-19, Ohhhh maaan <nobodyhere(a)example.com> wrote: >>> >>> I've used Linux years ago and I think I recall you could just type >>> linux single or linux emergency at the boot CD, but nothing works >>> with this new CentOS 5.x rescue CD. I'm stuck at "boot:" and nothing >>> I try just drops/boots me into a shell prompt. Please, help! :) >> >> Close: it's linux rescue, not emergency: >> >> >http://www.centos.org/docs/5/html/Installation_Guide-en-US/s1-rescuemode-boot.html >> >> But I believe the onscreen text tells you to hit F5 for help and >> other boot options, so you should look for that next time. See e.g. >> >> http://www.go2linux.org/pics/centos-base/Screenshot.png >> >> Hitting F5 gives you more information on booting the CD in rescue >> mode. >> >> --keith >> > >Yes, I know what it says. I did that already, and it just goes to the >same install screen. Doesn't matter if I type linux, linux text, linux >rescue, or just hit enter, or try linux single, linux emergency, or >anything else, it _always_ goes to the text menus and doesn't allow me >to break out of it or drop to a shell prompt, or anything else. It just >wants the install disk images. .... >The problem is, I'm 5,000 miles away working over a KVM. All I need to >do, is find this one thing so I fix this problem, and I just can't find >it. No one else seems to know. This strikes me as odd. Believe me, >trying to convince some DC tech that only power cycles systems to do >anything is not going to happen, so if anyone can help me find this one >trivial thing, it would be very appreciated. Are your (remote) keystrokes being mis-interpreted? Sounds rather like it only sees "Enter". Do you just need to edit a text file in an otherwise healthy filesystem? If you think the "rescue" aspect of the CD isn't working how about spinning up a generic live CD like Ubuntu, mounting the install, and editing the file? Bill -- William D Waddington william.waddington(a)beezmo.com "Even bugs...are unexpected signposts on the long road of creativity..." - Ken Burtch
From: Hans-Peter Diettrich on 19 May 2010 11:30 Ohhhh maaan schrieb: > I have a kernel panic and need to fix a typo. I don't have the install > disks, and I just want to use the CD to access the shell prompt so I > can run the commands need. I can't get to the grub boot loader screen. Can you still boot any live-CD, and apply your corrections from there? DoDi
From: Ohhhh maaan on 19 May 2010 15:21 unruh wrote: > On 2010-05-19, Ohhhh maaan <nobodyhere(a)example.com> wrote: >> Keith Keller wrote: >> >>> ["Followup-To:" header set to comp.os.linux.misc.] >>> >>> On 2010-05-19, Ohhhh maaan <nobodyhere(a)example.com> wrote: >>>> >>>> I've used Linux years ago and I think I recall you could just type >>>> linux single or linux emergency at the boot CD, but nothing works >>>> with this new CentOS 5.x rescue CD. I'm stuck at "boot:" and >>>> nothing I try just drops/boots me into a shell prompt. Please, >>>> help! :) >>> >>> Close: it's linux rescue, not emergency: >>> >>> >> http://www.centos.org/docs/5/html/Installation_Guide-en-US/s1-rescuemode-boot.html >>> >>> But I believe the onscreen text tells you to hit F5 for help and >>> other boot options, so you should look for that next time. See e.g. >>> >>> http://www.go2linux.org/pics/centos-base/Screenshot.png >>> >>> Hitting F5 gives you more information on booting the CD in rescue >>> mode. >>> >>> --keith >>> >> >> Yes, I know what it says. I did that already, and it just goes to the >> same install screen. Doesn't matter if I type linux, linux text, >> linux rescue, or just hit enter, or try linux single, linux >> emergency, or anything else, it _always_ goes to the text menus and >> doesn't allow me to break out of it or drop to a shell prompt, or >> anything else. It just >> wants the install disk images. In fact, the link you've provided >> says it all: >> >> "Once you have booted using one of the described methods, add the >> keyword rescue as a kernel parameter. For example, for an x86 system, >> type the following command at the installation boot prompt: >> >> >> linux rescue >> >> >> >> You are prompted to answer a few basic questions, including which >> language to use. It also prompts you to select where a valid rescue >> image is located. Select from Local CD-ROM, Hard Drive, NFS image, >> FTP, or HTTP. The location selected must contain a valid installation >> tree " >> >> It simply does not allow me to skip or select any options that allow >> me to even get to the point where I can get shell access. I >> definitely recall that the boot CD's allowed a person to jump right >> into a shell if they wanted, even without using the installed >> bootloader, and I can't find any information to show where someone >> can just boot from the CD's kernel and drop into a shell and run >> commands (it always wants the install images). > > Uh, the shell runs on top of the kernel. Yes, I know. > It MUST load a kernel to run > the shell, Yes, that is the point to the boot CD. > so tell it where to get tthe kernel so you can run the > shell. It will not boot another kernel, thus I'm locked into the rescue mode steps. This is the problem. So, do you know how to drop into shell after the rescue CD's kernel is loaded and not go through the rescue steps that want the CentOS images, so I can just drop into shell?
From: Ohhhh maaan on 19 May 2010 15:23
Bill Waddington wrote: > On Tue, 18 May 2010 23:39:54 -0700, Ohhhh maaan > <nobodyhere(a)example.com> wrote: > >>Keith Keller wrote: >> >>> ["Followup-To:" header set to comp.os.linux.misc.] >>> >>> On 2010-05-19, Ohhhh maaan <nobodyhere(a)example.com> wrote: >>>> >>>> I've used Linux years ago and I think I recall you could just type >>>> linux single or linux emergency at the boot CD, but nothing works >>>> with this new CentOS 5.x rescue CD. I'm stuck at "boot:" and >>>> nothing I try just drops/boots me into a shell prompt. Please, >>>> help! :) >>> >>> Close: it's linux rescue, not emergency: >>> >>> >>http://www.centos.org/docs/5/html/Installation_Guide-en-US/s1-rescuemode-boot.html >>> >>> But I believe the onscreen text tells you to hit F5 for help and >>> other boot options, so you should look for that next time. See e.g. >>> >>> http://www.go2linux.org/pics/centos-base/Screenshot.png >>> >>> Hitting F5 gives you more information on booting the CD in rescue >>> mode. >>> >>> --keith >>> >> >>Yes, I know what it says. I did that already, and it just goes to the >>same install screen. Doesn't matter if I type linux, linux text, linux >>rescue, or just hit enter, or try linux single, linux emergency, or >>anything else, it _always_ goes to the text menus and doesn't allow me >>to break out of it or drop to a shell prompt, or anything else. It >>just wants the install disk images. > > ... > >>The problem is, I'm 5,000 miles away working over a KVM. All I need to >>do, is find this one thing so I fix this problem, and I just can't >>find it. No one else seems to know. This strikes me as odd. Believe >>me, trying to convince some DC tech that only power cycles systems to >>do anything is not going to happen, so if anyone can help me find this >>one trivial thing, it would be very appreciated. > > Are your (remote) keystrokes being mis-interpreted? Sounds rather > like it only sees "Enter". That is possible, but I don't think so. It seems that so long as I type "linux" before anything else, it will go into text or graphical mode. > Do you just need to edit a text file in an otherwise healthy > filesystem? Yes, but the issue is the installed kernel. I need to just run grub for it. > If you think the "rescue" aspect of the CD isn't working > how about spinning up a generic live CD like Ubuntu, mounting the > install, and editing the file? I would certainly consider this, if this were an option at the DC. It might be, but I suppose this is my question; Can you just do this from a rescue CD? I used to do it in RH 4, etc. a long time ago, so does that option/method not exist now? So, I need a live CD, not a rescue CD? |