Berkeley-Sysadmin_DeCal - Lab3a
作者学习的版本为spring 2021，但近年的作业内容基本一致
Q1
Developer: Pierre Schmitz
Fingerprint: 3E80 CA1A 8B89 F69C BA57 D98A 76A5 EF90 5444 9A5C
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gpg: assuming signed data in 'archlinux-2024.02.01-x86_64.iso'
gpg: Signature made Thu Feb 1 12:10:46 2024 UTC
gpg: using EDDSA key 3E80CA1A8B89F69CBA57D98A76A5EF9054449A5C
gpg: issuer "[email protected]"
gpg: /root/.gnupg/trustdb.gpg: trustdb created
gpg: key 76A5EF9054449A5C: public key "Pierre Schmitz <[email protected]>" imported
gpg: key 7F2D434B9741E8AC: public key "Pierre Schmitz <[email protected]>" imported
gpg: Total number processed: 2
gpg: imported: 2
gpg: no ultimately trusted keys found
gpg: Good signature from "Pierre Schmitz <[email protected]>" [unknown]
gpg: WARNING: This key is not certified with a trusted signature!
gpg: There is no indication that the signature belongs to the owner.
Primary key fingerprint: 3E80 CA1A 8B89 F69C BA57 D98A 76A5 EF90 5444 9A5C
Q2
Hostname: arches
IP address: 192.168.122.29
Q3
EFI System Partition
The EFI System Partition is used by computers with UEFI firmware to store boot loaders, device drivers, and other files required to start the operating system. It’s a dedicated partition that allows the UEFI firmware to access and launch the operating system and its utilities before the OS itself starts. This partition is essential for the boot process in modern computing environments that use UEFI instead of traditional BIOS.
Swap Partition
The swap partition serves as overflow space for your computer’s RAM. If your system runs out of physical memory (RAM), it can move inactive pages of memory to the swap partition to free up RAM for active processes. This can prevent the system from crashing due to memory exhaustion, especially in situations where RAM is limited. However, accessing data on the swap partition is slower than accessing RAM, so while it increases the system’s capacity for handling memory, it can also lead to slower performance if relied upon too heavily.
Q4
sdb4
Q5
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Disk /dev/sda: 5 GiB, 5368709120 bytes, 10485760 sectors
Disk model: QEMU HARDDISK
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: gpt
Disk identifier: B9D6D4CB-DCAA-4C71-B870-5EDF998A5D93
Device Start End Sectors Size Type
/dev/sda1 2048 1050623 1048576 512M EFI System
/dev/sda2 1050624 9437183 8386560 4G Linux filesystem
/dev/sda3 9437184 10483711 1046528 511M Linux swap
Q6
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NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINTS
loop0 7:0 0 766.5M 1 loop /run/archiso/airootfs
sda 8:0 0 5G 0 disk
├─sda1 8:1 0 512M 0 part
├─sda2 8:2 0 4G 0 part
│ └─cryptroot 254:0 0 4G 0 crypt
└─sda3 8:3 0 511M 0 part
sr0 11:0 1 932.3M 0 rom /run/archiso/bootmnt
Q7
the mkfs.fat -F32 /dev/sda1 command.
Difference
mkfs.fat -F32 formats the partition with the FAT32 filesystem, while mkfs.ext4 formats with the Ext4 filesystem. /dev/sda1 is likely a primary partition, whereas /dev/mapper/cryptroot suggests an encrypted logical volume.
Why
The mkfs.fat command is used to format a boot partition, which doesn’t require the advanced features of Ext4 and needs to be readable by the system’s firmware (like UEFI) to boot the system. The mkfs.ext4 command is used for the main system partition where the Linux operating system and its files will reside.
Q8
You can see every single filesystem that’s currently mounted by running the mount command. Run it, and look for the two filesystems we just mounted.
Answer
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/dev/mapper/cryptroot on /mnt type ext4 (rw,relatime)
/dev/sda1 on /mnt/boot type vfat (rw,relatime,fmask=0022,dmask=0022,codepage=437,iocharset=ascii,shortname=mixed,utf8,errors=remount-ro)
Q9
Q10
hostname -f: arch
ip addr:
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1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host noprefixroute
valid_lft forever preferred_lft forever
2: ens2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
link/ether 52:54:00:19:b5:ce brd ff:ff:ff:ff:ff:ff
altname enp0s2
inet 192.168.122.172/24 brd 192.168.122.255 scope global dynamic noprefixroute ens2
valid_lft 3518sec preferred_lft 3068sec
inet6 fe80::a59:6c7d:ff7d:16eb/64 scope link
valid_lft forever preferred_lft forever
mount:
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proc on /proc type proc (rw,nosuid,nodev,noexec,relatime)
sys on /sys type sysfs (rw,nosuid,nodev,noexec,relatime)
dev on /dev type devtmpfs (rw,nosuid,relatime,size=481452k,nr_inodes=120363,mode=755,inode64)
run on /run type tmpfs (rw,nosuid,nodev,relatime,mode=755,inode64)
efivarfs on /sys/firmware/efi/efivars type efivarfs (rw,nosuid,nodev,noexec,relatime)
/dev/mapper/cryptroot on / type ext4 (rw,relatime)
securityfs on /sys/kernel/security type securityfs (rw,nosuid,nodev,noexec,relatime)
tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev,inode64)
devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000)
cgroup2 on /sys/fs/cgroup type cgroup2 (rw,nosuid,nodev,noexec,relatime,nsdelegate,memory_recursiveprot)
pstore on /sys/fs/pstore type pstore (rw,nosuid,nodev,noexec,relatime)
bpf on /sys/fs/bpf type bpf (rw,nosuid,nodev,noexec,relatime,mode=700)
systemd-1 on /proc/sys/fs/binfmt_misc type autofs (rw,relatime,fd=37,pgrp=1,timeout=0,minproto=5,maxproto=5,direct,pipe_ino=1804)
hugetlbfs on /dev/hugepages type hugetlbfs (rw,nosuid,nodev,relatime,pagesize=2M)
mqueue on /dev/mqueue type mqueue (rw,nosuid,nodev,noexec,relatime)
debugfs on /sys/kernel/debug type debugfs (rw,nosuid,nodev,noexec,relatime)
tracefs on /sys/kernel/tracing type tracefs (rw,nosuid,nodev,noexec,relatime)
fusectl on /sys/fs/fuse/connections type fusectl (rw,nosuid,nodev,noexec,relatime)
configfs on /sys/kernel/config type configfs (rw,nosuid,nodev,noexec,relatime)
systemd-1 on /boot type autofs (rw,relatime,fd=52,pgrp=1,timeout=120,minproto=5,maxproto=5,direct,pipe_ino=2904)
tmpfs on /tmp type tmpfs (rw,nosuid,nodev,nr_inodes=1048576,inode64)
/dev/sda1 on /boot type vfat (rw,nosuid,nodev,noexec,relatime,nosymfollow,fmask=0077,dmask=0077,codepage=437,iocharset=ascii,shortname=mixed,utf8,errors=remount-ro)
tmpfs on /run/user/0 type tmpfs (rw,nosuid,nodev,relatime,size=98444k,nr_inodes=24611,mode=700,inode64)
lsblk:
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NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINTS
sda 8:0 0 5G 0 disk
├─sda1 8:1 0 512M 0 part
├─sda2 8:2 0 4G 0 part
│ └─cryptroot 254:0 0 4G 0 crypt /
└─sda3 8:3 0 511M 0 part [SWAP]
sr0 11:0 1 1024M 0 rom
uname -a:
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Linux arch 6.7.6-arch1-1 #1 SMP PREEMPT_DYNAMIC Fri, 23 Feb 2024 16:31:48 +0000 x86_64 GNU/Linux
Some Tips
Tip One
The command used to create the VM provided by the lab is:
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sudo virt-install --name archvm --memory 575 --cpu host --vcpus 1 --disk size=5 --network network=default --boot uefi --graphics none --cdrom archlinux-2021.09.01-x86_64.iso
But the creation will run into error since current available versions of arch linux is much larger, which results in larger memory cost. So I recommend you to allocate at least 1 GB memory for the vm.
Tip Two
You’d better do network configuration and management during the installation, which may become little tricky after you reboot your system. In my case, I need to install dhcpcd during installation, so that I can install inetutils to use hostname command after boot.