On 9/27/21 03:56, hermann.la...@uni-heidelberg.de wrote: > Hi Stan, > > On Sat, Sep 25, 2021 at 11:34:59PM -0600, Stan Johnson wrote: >> Not knowing what the preferred size should be for a GRUB /boot >> partition, I decided to let Guided Partioning use its defaults for >> /dev/sda. As I recall, the partitioner warned that the number of >> cylinders on the disk exceeded the maximum of 65536, but the creation of >> filesystems and the rest of the installation proceeded anyway, without >> any other noticeable errors. >> >> The layout for /dev/sda is as follows: >> >> # fdisk -l /dev/sda >> Disk /dev/sda: 136.73 GiB, 146815737856 bytes, 286749488 sectors >> Disk model: ST3146807LC >> Geometry: 255 heads, 2 sectors/track, 37965 cylinders >> Units: sectors of 1 * 512 = 512 bytes >> Sector size (logical/physical): 512 bytes / 512 bytes >> I/O size (minimum/optimal): 512 bytes / 512 bytes >> Disklabel type: sun >> >> Device Start End Sectors Size Id Type Flags >> /dev/sda1 0 1000109 1000110 488.3M 1 Boot >> /dev/sda2 1000110 284748299 283748190 135.3G 83 Linux native >> /dev/sda3 0 286749029 286749030 136.7G 5 Whole disk >> /dev/sda4 284748300 286749029 2000730 976.9M 82 Linux swap > > this is a sun disk partitioning scheme - not shure, if this is well supported > with grub. > >> -> Question 1: If I don't plan to install Solaris, is it safe to remove >> the "Whole disk" partition (/dev/sda3)? > > AFAIR sun disklabels allows up to 8 entries - so there is no advantage in > removing the solaris standard whole disk entry. >
I have had no issues with GRUB and Sun type disk labels and "vtoc" data. Also there are four bits used to count the disk "slices" but it depends on if one is on Sparc or x86 to get all four bits. So really one may have 16 separate entries in the disk vtoc but it won't be portable across architectures. I don't even know if that was ever documented. I have not even tried that for a few decades. I am quite sure that one may have eight disk regions without issue and they may overlap one another. That results in the old "backup" slice. -- Dennis Clarke RISC-V/SPARC/PPC/ARM/CISC UNIX and Linux spoken GreyBeard and suspenders optional
