Hostname
$ hostname
jumphost
# all FQDN's (check 'search' field in /etc/resolv.conf)
$ hostname -A
jumphost.b.google.internal
# addresses for the host namea
$ hostname -i
10.31.30.10
Kernel name, hostname, processor, operating system
$ uname -a
Linux jumphost 4.19.0-19-cloud-amd64 #1 SMP Debian 4.19.232-1 (2022-03-07) x86_64 GNU/Linux
$ lscpu
Architecture: x86_64
CPU op-mode(s): 32-bit, 64-bit
Byte Order: Little Endian
Address sizes: 46 bits physical, 48 bits virtual
CPU(s): 2
On-line CPU(s) list: 0,1
Thread(s) per core: 2
[...]
$ cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 79
model name : Intel(R) Xeon(R) CPU @ 2.20GHz
stepping : 0
microcode : 0x1
cpu MHz : 2199.998
cache size : 56320 KB
[...]
processor : 1
vendor_id : GenuineIntel
cpu family : 6
model : 79
model name : Intel(R) Xeon(R) CPU @ 2.20GHz
stepping : 0
microcode : 0x1
cpu MHz : 2199.998
cache size : 56320 KB
[...]
# RAID info
$ cat /proc/mdstat
Distribution details
$ lsb_release -a
No LSB modules are available.
Distributor ID: Debian
Description: Debian GNU/Linux 10 (buster)
Release: 10
Codename: buster
$ cat /etc/os-release
PRETTY_NAME="Debian GNU/Linux 10 (buster)"
NAME="Debian GNU/Linux"
VERSION_ID="10"
VERSION="10 (buster)"
VERSION_CODENAME=buster
ID=debian
HOME_URL="https://www.debian.org/"
SUPPORT_URL="https://www.debian.org/support"
BUG_REPORT_URL="https://bugs.debian.org/"
Process list
$ pstree
systemd-+-agent---9*[{agent}]
|-2*[agetty]
|-auditd---{auditd}
|-cron
|-dbus-daemon
|-dhclient
|-google_guest_ag---8*[{google_guest_ag}]
|-google_osconfig---8*[{google_osconfig}]
|-haveged
|-ntpd---{ntpd}
|-packagekitd---2*[{packagekitd}]
|-polkitd---2*[{polkitd}]
|-process-agent---8*[{process-agent}]
|-rsyslogd---3*[{rsyslogd}]
|-sshd-+-2*[sshd---sshd---bash]
| |-sshd---sshd---zsh---sudo---su---bash---pstree
| |-sshd---sshd
| `-sshd---sshd---kubectl---7*[{kubectl}]
|-stackdriver-col---stackdriver-col---12*[{stackdriver-col}]
|-3*[systemd---(sd-pam)]
|-systemd-journal
|-systemd-logind
|-systemd-udevd
|-tinyproxy---10*[tinyproxy]
|-trace-agent---8*[{trace-agent}]
|-unattended-upgr---{unattended-upgr}
|-zsh---gitstatusd-linu---4*[{gitstatusd-linu}]
`-2*[zsh]
Docker
# show all containers (stopped ones as well)
$ docker ps -a
[ ... ]
Crontabs
$ crontab -l
no crontab for bob
# crontabs for all users
# ls -la /var/spool/cron/crontabs/
total 16
drwx-wx--T 2 root crontab 4096 Feb 16 2022 .
drwxr-xr-x 3 root root 4096 Feb 16 2021 ..
-rw------- 1 bob crontab 1174 Feb 16 2022 bob
$ ls -la /etc/ | grep cron
drwxr-xr-x 2 root root 4096 Mar 22 2022 cron.d
drwxr-xr-x 2 root root 4096 May 26 06:17 cron.daily
drwxr-xr-x 2 root root 4096 Feb 16 2021 cron.hourly
drwxr-xr-x 2 root root 4096 Feb 16 2021 cron.monthly
drwxr-xr-x 2 root root 4096 Feb 16 2021 cron.weekly
-rw-r--r-- 1 root root 1042 Oct 11 2019 crontab
Name servers (DNS)
$ nslookup prezydent.pl
Server: 169.254.169.254
Address: 169.254.169.254#53
Non-authoritative answer:
Name: prezydent.pl
Address: 172.67.10.17
Name: prezydent.pl
Address: 104.22.38.232
Name: prezydent.pl
Address: 104.22.39.23
$ cat /etc/resolv.conf
nameserver 169.254.169.254
Routing
$ ip r s
default via 10.31.30.1 dev ens4
10.31.30.1 dev ens4 scope link
$ route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 10.31.30.1 0.0.0.0 UG 0 0 0 ens4
10.31.30.1 0.0.0.0 255.255.255.255 UH 0 0 0 ens4
Network interfaces
$ ifconfig -a
ens4: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1460
inet 10.31.30.10 netmask 255.255.255.255 broadcast 10.31.30.10
inet6 fe80::aff:fe1f:1e0a prefixlen 64 scopeid 0x20<link>
ether 42:01:0a:1f:1e:0a txqueuelen 1000 (Ethernet)
RX packets 145905643 bytes 512380185405 (477.1 GiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 133263861 bytes 82742313864 (77.0 GiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 1000 (Local Loopback)
RX packets 126771002 bytes 18588316602 (17.3 GiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 126771002 bytes 18588316602 (17.3 GiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
Firewall
$ iptables-save
# Generated by iptables-save v1.8.7 on Tue Oct 11 16:56:06 2022
*filter
:INPUT ACCEPT [0:0]
:FORWARD DROP [0:0]
:OUTPUT ACCEPT [0:0]
:DOCKER - [0:0]
:DOCKER-ISOLATION-STAGE-1 - [0:0]
:DOCKER-ISOLATION-STAGE-2 - [0:0]
:DOCKER-USER - [0:0]
-A FORWARD -j DOCKER-USER
-A FORWARD -j DOCKER-ISOLATION-STAGE-1
-A FORWARD -o br-65cfc1a5890f -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
COMMIT
# Completed on Tue Oct 11 16:56:06 2022
# Generated by iptables-save v1.8.7 on Tue Oct 11 16:56:06 2022
*nat
:PREROUTING ACCEPT [0:0]
:INPUT ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
:POSTROUTING ACCEPT [0:0]
:DOCKER - [0:0]
-A PREROUTING -m addrtype --dst-type LOCAL -j DOCKER
-A OUTPUT ! -d 127.0.0.0/8 -m addrtype --dst-type LOCAL -j DOCKER
-A DOCKER ! -i br-65cfc1a5890f -p tcp -m tcp --dport 443 -j DNAT --to-destination 172.20.0.3:443
-A DOCKER ! -i br-65cfc1a5890f -p tcp -m tcp --dport 80 -j DNAT --to-destination 172.20.0.3:80
COMMIT
# Completed on Tue Oct 11 16:56:06 2022
Time & date
$ date
Tue May 11 16:26:28 UTC 2022
Memory
$ free -m
total used free shared buff/cache available
Mem: 1992 541 988 20 462 1275
Swap: 0 0 0
Storage
$ df -h
Filesystem Size Used Avail Use% Mounted on
udev 988M 0 988M 0% /dev
tmpfs 200M 21M 179M 11% /run
/dev/sda1 30G 17G 12G 61% /
tmpfs 997M 0 997M 0% /dev/shm
tmpfs 5.0M 0 5.0M 0% /run/lock
tmpfs 997M 0 997M 0% /sys/fs/cgroup
/dev/sda15 124M 5.9M 118M 5% /boot/efi
$ lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 30G 0 disk
|-sda1 8:1 0 29.9G 0 part /
|-sda14 8:14 0 3M 0 part
`-sda15 8:15 0 124M 0 part /boot/ef
$ cat /etc/fstab
# /etc/fstab: static file system information
UUID=2af9b9e0-f31f-4f6c-8245-fba3fa511c66 / ext4 rw,discard,errors=remount-ro,x-systemd.growfs 0 1
UUID=164A-AEA1 /boot/efi vfat defaults 0 0
$ blkid
/dev/sda1: UUID="2af9b9e0-f31f-4f6c-8245-fba3fa511c66" TYPE="ext4" PARTUUID="1165fbaa-f9b2-414f-bf97-59191a1c8654"
/dev/sda14: PARTUUID="fb1f4866-67d3-2948-8b85-07d8cc0a429d"
/dev/sda15: SEC_TYPE="msdos" UUID="164A-AEA1" TYPE="vfat" PARTUUID="e2b0a385-c802-0345-bd6c-839c40cc674e"
$ fdisk -l
Disk /dev/sda: 30 GiB, 32212254720 bytes, 62914560 sectors
Disk model: PersistentDisk
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Disk identifier: 3948AFEB-2993-D54E-A66C-392005D28B38
Device Start End Sectors Size Type
/dev/sda1 262144 62914526 62652383 29.9G Linux filesystem
/dev/sda14 2048 8191 6144 3M BIOS boot
/dev/sda15 8192 262143 253952 124M EFI System
Partition table entries are not in disk order.
#swap info
$ cat /proc/swaps
Filename Type Size Used Priority
# NFS
$ cat /etc/exports
cat: /etc/exports: No such file or directoryl
# logical volumes
$ lvs
# groups
$ vgs
# physical devices
$ pvs
$ mount | grep -v cgroup | column -t
sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,relatime)
proc on /proc type proc (rw,nosuid,nodev,noexec,relatime)
udev on /dev type devtmpfs (rw,nosuid,relatime,size=1011104k,nr_inodes=252776,mode=755)
devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000)
tmpfs on /run type tmpfs (rw,nosuid,noexec,relatime,size=204080k,mode=755)
/dev/sda1 on / type ext4 (rw,relatime,discard,errors=remount-ro)
securityfs on /sys/kernel/security type securityfs (rw,nosuid,nodev,noexec,relatime)
Systemd services
$ systemctl --all --type=service list-unit-files
UNIT FILE STATE
proc-sys-fs-binfmt_misc.automount static
-.mount generated
boot-efi.mount generated
dev-hugepages.mount static
dev-mqueue.mount static
proc-sys-fs-binfmt_misc.mount static
systemd-ask-password-wall.path static
apparmor.service enabled
apt-daily-upgrade.service static
apt-daily.service static
auditd.service enabled
[email protected] enabled
Bash history
$ history -w /dev/stdout | sort | uniq -c | sort -nr | head
46 exit
27 ls -la
11 apt update
10 cd ..
Startup services
$ runlevel
N 5
$ ls /etc/rc5.d/
S01auditd S01chrony S01cron S01dbus S01haveged S01ntp S01rsyslog S01saned S01ssh S01stackdriver-agent S01sudo S01sysstat S01tinyproxy S01unattended-upgrades
Hardware info
$ lshw
jumphost
description: Computer
product: Google Compute Engine
vendor: Google
serial: GoogleCloud-F99EA9D2F727207E633234F62763D
width: 64 bits
capabilities: smbios-2.4 dmi-2.4 smp vsyscall32
configuration: boot=normal uuid=F99EA9D2-F7f7-2062-A7E6-33234F62763D
*-core
description: Motherboard
product: Google Compute Engine
vendor: Google
physical id: 0
serial: Board-GoogleCloud-F99EA9D2F7277E633234F62763D
*-firmware
description: BIOS
vendor: Google
physical id: 0
version: Google
date: 01/01/2011
size: 96KiB
[...]
# list all PCI devices
$ lspci
00:00.0 Host bridge: Intel Corporation 440FX - 82441FX PMC [Natoma] (rev 02)
00:01.0 ISA bridge: Intel Corporation 82371AB/EB/MB PIIX4 ISA (rev 03)
00:01.3 Bridge: Intel Corporation 82371AB/EB/MB PIIX4 ACPI (rev 03)
00:03.0 Non-VGA unclassified device: Red Hat, Inc Virtio SCSI
00:04.0 Ethernet controller: Red Hat, Inc Virtio network device
00:05.0 Unclassified device [00ff]: Red Hat, Inc Virtio memory balloon
00:06.0 Unclassified device [00ff]: Red Hat, Inc Virtio RNG