On Mon, February 1, 2016 1:56 pm, Valeri Galtsev wrote: > > On Mon, February 1, 2016 1:33 pm, m.roth at 5-cent.us wrote: >> Excerpt: >> Running rm -rf / on any UEFI Linux distribution can potentially >> perma-brick your system. > > Yes, I kind of like "rm -rf /". If my memory doesn't fail me, long ago it > was one of the tricky questions in sysadmin exam (not that anymore if I > read what you, Michael, write further correctly...). Anyway, let's imagine > we are back then, then what > > rm -rf / > > will do you your system? How dramatic this command is? > > Well, it definitely will obliterate your /etc with all your settings. Then > it will start deleting /dev, and once it deletes the block device your > root filesystem "/" lives on, all trouble ends there. So, you just take > your drive, and you will be able to mount on different machine /home, > /usr, /var and what's left of your / partition. /etc is gone, bit this > only as dramatic as it gets (thanks for alphabetical order the command > follows). I just discovered that I couldn't even re-cite alphabet correctly today: it is /bin that you loose, but /etc alphabetically goes after /dev, so will not even loose your /etc, all you will need it to restore portion of your /dev and the whole /bib (which you can do easily if you have "twin" system around...) > > Sorry about long spam message, everybody. I just so liked that tricky > question from my past, I couldn't hold myself. > > Valeri > >> >> As a public service announcement, recursively removing all of your files >> from / is no longer recommended. On UEFI distributions by default where >> EFI variables are accessible via /sys, this can now mean trashing your >> UEFI implementation. >> >> There is this systemd bug report requesting that UEFI variables be >> mounted >> as read-only by default. Lennart Poettering had initially responded and >> simply said, "Well, there are tools that actually want to write it. We >> also expose /dev/sda accessible for root, even though it can be used to >> hose your system. The ability to hose a system is certainly reason >> enought >> to make sure it's well protected and only writable to root. But beyond >> that: root can do anything really." He then closed the ticket. >> --- end excerpt --- >> >> <http://www.phoronix.com/scan.php?page=news_item&px=UEFI-rm-root-directory> >> >> "And they closed the ticket"? That tuxedo on the cockroach is so >> elegent! >> >> Ok, *now* tell me why we shouldn't hate systemd? >> >> mark >> >> _______________________________________________ >> CentOS mailing list >> CentOS at centos.org >> https://lists.centos.org/mailman/listinfo/centos >> > > > ++++++++++++++++++++++++++++++++++++++++ > Valeri Galtsev > Sr System Administrator > Department of Astronomy and Astrophysics > Kavli Institute for Cosmological Physics > University of Chicago > Phone: 773-702-4247 > ++++++++++++++++++++++++++++++++++++++++ > _______________________________________________ > CentOS mailing list > CentOS at centos.org > https://lists.centos.org/mailman/listinfo/centos > ++++++++++++++++++++++++++++++++++++++++ Valeri Galtsev Sr System Administrator Department of Astronomy and Astrophysics Kavli Institute for Cosmological Physics University of Chicago Phone: 773-702-4247 ++++++++++++++++++++++++++++++++++++++++