Grub Legacy On CentOS 7

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Hello Everyone,

We have CentOS6 server. And we are planning to upgrade it to CentOS7.And GRUB 2 needs a new bios grub partition. Creating a new partition is too much risky. I am wondering if it is possible to replace Grub2 with Grub legacy on CentOS7 machine?

Thanks!!
Sachin

5 thoughts on - Grub Legacy On CentOS 7

  • I would build the CentOS 7 machine on new hardware, bring it up in parallel, then cut your applications over to it, and redeploy the old hardware as something else.

  • BIOS boot partition is only necessary on GPT partitioned disks. For MBR partitioned disks, the GRUB 2 core.img goes into the MBR gap, the same as before. On rare occasion when the 1st partition starts at LBA
    63 the core.img can’t fit into the gap. The supported work around is repartitioning such that 1st partition starts at LBA 2048. The less supported and recommended work around is to use grub2-install with -f

    It really isn’t. You can use gparted to resize/move the /boot partition/volume safely and fast. And if it blows up just reformat it it in the installer which isn’t a bad idea to do anyway. There’s no need to keep an old CentOS 6 /boot partition around anyway.

    Yeah just yum erase grub2 and then force the installation of the CentOS 6 grub package; then run grub-install.

  • It is definitely possible to use GRUB legacy with CentOS 7. I do it on several systems. Note that there is a bug in the current EL 7 version of grubby which causes the initrd line to not be added to the stanza of newly installed kernels.

    Always check /etc/grub.conf before rebooting to a newly installed kernel, particularly when doing so remotely. :-/

  • Hello Everyone,

    I am trying to use GRUB legacy with CentOS 7. And it is giving me following error.

    systemd-fsck: fsck error 2(no such file or directory) while executing fsck.ext3 for /dev/sda5
    mount:unknown file system type ‘ext3’.

    Has anyone seen this error ?

    Thanks Sachin