Linux

Google SDK SSH Mac Terminal

February 14, 2022 by Ulysses

I’m having trouble logging in using Google SDK Compute SSH on a Mac Terminal.

Here’s the fix.

gcloud compute ssh USERNAME@SERVER --zone ZONE --project PROJECTID --internal-ip 2>&1

There was an issue with a redirect to another shell.

AWS SDK Load Config

February 14, 2022 by Ulysses

Occasionally I was getting this random error when running Terraform.

╷
│ Error: error configuring Terraform AWS Provider: no valid credential sources for Terraform AWS Provider found.
│ 
│ Please see https://registry.terraform.io/providers/hashicorp/aws
│ for more information about providing credentials.
│ 
│ Error: RequestError: send request failed
│ caused by: Post "https://sts.amazonaws.com/": read tcp xx.xx.xx.xx:59422->xx.xx.xx.xx:443: read: connection reset by peer
│ 
│ 
│   with provider["registry.terraform.io/hashicorp/aws"],
│   on main.tf line 10, in provider "aws":
│   10: provider "aws" {

Here’s the fix. Place this in your ~/.bash_profile.

export AWS_SDK_LOAD_CONFIG=1

This forces Terraform to use both config and credentials file.

Saml2aws

February 14, 2022 by Ulysses

Use Saml2Aws CLI as an alternative to SAML to AWS STS Key Conversion.

Install on Mac.

brew install saml2aws
saml2aws --version

Configure. Provide information.

saml2aws configure

It will create a ~/.saml2aws config file. Set session to 8 hours.

aws_session_duration    = 28800

saml2aws login

After authentication and/or MFA, your ~/.aws/credentials will be updated.

Linux prompt display current directory only

February 11, 2022 by Ulysses

Here’s the command to display only the current directory.

export PROMPT_DIRTRIM=1

Place the command in your ~/.bashrc to make it permanent.

SFTP Command Line

February 6, 2022 by Ulysses

Here are command lines you can within SFTP.

sftp username@servername

Commands available from the local client.

lls
lcd
lmkdir
lpwd
lumask

Commands available on remote server.

cd
chmod
chown
exit
get
help
ln
ls
mkdir
put
pwd
rename
rm
rmdir
version
!

Extend LVM Logical Volume

February 5, 2022 by Ulysses

How to extend a LVM logical volume.

Extend the physical drive.

gcloud compute disks resize data-drive --size=40GB

SSH to a server and extend the physical volume.

$ pvresize /dev/sdb
  Physical volume "/dev/sdb" changed
  1 physical volume(s) resized or updated / 0 physical volume(s) not resized

$ pvs
  PV         VG Fmt  Attr PSize   PFree 
  /dev/sdb   vg lvm2 a--  <40.00g 10.00g

$ vgs
  VG #PV #LV #SN Attr   VSize   VFree 
  vg   1   1   0 wz--n- <40.00g 10.00g

$ lvs
  LV   VG Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  data vg -wi-ao---- <30.00g

Extend the logical volume.

$ lvresize -l +100%FREE /dev/vg/data
  Size of logical volume vg/data changed from <30.00 GiB (7679 extents) to <40.00 GiB (10239 extents).
  Logical volume vg/data successfully resized.

Check the volume size.

$ lsblk
NAME      MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sda         8:0    0   20G  0 disk 
├─sda1      8:1    0  200M  0 part /boot/efi
└─sda2      8:2    0 19.8G  0 part /
sdb         8:16   0   40G  0 disk 
└─vg-data 253:0    0   40G  0 lvm  /mnt

Still at 30GB.

$ df -Th
Filesystem          Type      Size  Used Avail Use% Mounted on
devtmpfs            devtmpfs  385M     0  385M   0% /dev
tmpfs               tmpfs     403M     0  403M   0% /dev/shm
tmpfs               tmpfs     403M  5.5M  398M   2% /run
tmpfs               tmpfs     403M     0  403M   0% /sys/fs/cgroup
/dev/sda2           xfs        20G  2.9G   17G  15% /
/dev/sda1           vfat      200M  5.8M  195M   3% /boot/efi
/dev/mapper/vg-data xfs        30G  247M   30G   1% /mnt
tmpfs               tmpfs      81M     0   81M   0% /run/user/1001

Extend the file system.

$ xfs_growfs /dev/vg/data
meta-data=/dev/mapper/vg-data    isize=512    agcount=12, agsize=655360 blks
         =                       sectsz=4096  attr=2, projid32bit=1
         =                       crc=1        finobt=1, sparse=1, rmapbt=0
         =                       reflink=1
data     =                       bsize=4096   blocks=7863296, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0, ftype=1
log      =internal log           bsize=4096   blocks=2560, version=2
         =                       sectsz=4096  sunit=1 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
data blocks changed from 7863296 to 10484736

Let’s check again.

$ df -Th
Filesystem          Type      Size  Used Avail Use% Mounted on
devtmpfs            devtmpfs  385M     0  385M   0% /dev
tmpfs               tmpfs     403M     0  403M   0% /dev/shm
tmpfs               tmpfs     403M  5.5M  398M   2% /run
tmpfs               tmpfs     403M     0  403M   0% /sys/fs/cgroup
/dev/sda2           xfs        20G  2.9G   17G  15% /
/dev/sda1           vfat      200M  5.8M  195M   3% /boot/efi
/dev/mapper/vg-data xfs        40G  319M   40G   1% /mnt
tmpfs               tmpfs      81M     0   81M   0% /run/user/1001

The logical volume is now at 40GB.

Setup LVM on a VM

February 5, 2022 by Ulysses

How to setup Logical Volume Manager on a VM.

Install LVM.

yum install lvm2

Check the disks available. We are going to run LVM on /dev/sdb.

$ lsblk
NAME   MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sda      8:0    0   20G  0 disk 
├─sda1   8:1    0  200M  0 part /boot/efi
└─sda2   8:2    0 19.8G  0 part /
sdb      8:16   0   20G  0 disk

Create a physical volume on /dev/sdb.

$ pvcreate /dev/sdb
  Physical volume "/dev/sdb" successfully created.
$ pvs
  PV         VG Fmt  Attr PSize   PFree
  /dev/sdb   vg lvm2 a--  <20.00g    0

Create a volume group called vg.

$ vgcreate vg /dev/sdb
  Volume group "vg" successfully created
$ vgs
  VG #PV #LV #SN Attr   VSize   VFree  
  vg   1   0   0 wz--n- <20.00g <20.00g

Create a 10GB logical volume group called data.

$ lvcreate -L 10G -n data vg
  Logical volume "data" created.
$ lvs
  LV   VG Attr       LSize  Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  data vg -wi-a----- 10.00g

Format the volume group and mount it.

$ mkfs.xfs /dev/vg/data
meta-data=/dev/vg/data           isize=512    agcount=4, agsize=655360 blks
         =                       sectsz=4096  attr=2, projid32bit=1
         =                       crc=1        finobt=1, sparse=1, rmapbt=0
         =                       reflink=1
data     =                       bsize=4096   blocks=2621440, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0, ftype=1
log      =internal log           bsize=4096   blocks=2560, version=2
         =                       sectsz=4096  sunit=1 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
Discarding blocks...Done.
$ mount /dev/vg/data /mnt

Check your logical volume. It says 10GB.

$ df -Th
Filesystem          Type      Size  Used Avail Use% Mounted on
devtmpfs            devtmpfs  385M     0  385M   0% /dev
tmpfs               tmpfs     403M     0  403M   0% /dev/shm
tmpfs               tmpfs     403M  5.5M  398M   2% /run
tmpfs               tmpfs     403M     0  403M   0% /sys/fs/cgroup
/dev/sda2           xfs        20G  2.9G   17G  15% /
/dev/sda1           vfat      200M  5.8M  195M   3% /boot/efi
tmpfs               tmpfs      81M     0   81M   0% /run/user/1000
/dev/mapper/vg-data xfs        10G  104M  9.9G   2% /mnt

Let’s now extend the logical volume to 20GB.

$ lvextend -l +100%FREE /dev/vg/data
  Size of logical volume vg/data changed from 10.00 GiB (2560 extents) to <20.00 GiB (5119 extents).
  Logical volume vg/data successfully resized.

Although lsblk says 20GB, our logical volume still says 10GB.

$ lsblk
NAME      MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sda         8:0    0   20G  0 disk 
├─sda1      8:1    0  200M  0 part /boot/efi
└─sda2      8:2    0 19.8G  0 part /
sdb         8:16   0   20G  0 disk 
└─vg-data 253:0    0   20G  0 lvm  /mnt
$ df -Th
Filesystem          Type      Size  Used Avail Use% Mounted on
devtmpfs            devtmpfs  385M     0  385M   0% /dev
tmpfs               tmpfs     403M     0  403M   0% /dev/shm
tmpfs               tmpfs     403M  5.5M  398M   2% /run
tmpfs               tmpfs     403M     0  403M   0% /sys/fs/cgroup
/dev/sda2           xfs        20G  2.9G   17G  15% /
/dev/sda1           vfat      200M  5.8M  195M   3% /boot/efi
tmpfs               tmpfs      81M     0   81M   0% /run/user/1000
/dev/mapper/vg-data xfs        10G  104M  9.9G   2% /mnt

We need to grow the file system.

$ xfs_growfs /dev/vg/data
meta-data=/dev/mapper/vg-data    isize=512    agcount=4, agsize=655360 blks
         =                       sectsz=4096  attr=2, projid32bit=1
         =                       crc=1        finobt=1, sparse=1, rmapbt=0
         =                       reflink=1
data     =                       bsize=4096   blocks=2621440, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0, ftype=1
log      =internal log           bsize=4096   blocks=2560, version=2
         =                       sectsz=4096  sunit=1 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
data blocks changed from 2621440 to 5241856

Let’s check again.

$ df -Th
Filesystem          Type      Size  Used Avail Use% Mounted on
devtmpfs            devtmpfs  385M     0  385M   0% /dev
tmpfs               tmpfs     403M     0  403M   0% /dev/shm
tmpfs               tmpfs     403M  5.5M  398M   2% /run
tmpfs               tmpfs     403M     0  403M   0% /sys/fs/cgroup
/dev/sda2           xfs        20G  2.9G   17G  15% /
/dev/sda1           vfat      200M  5.8M  195M   3% /boot/efi
tmpfs               tmpfs      81M     0   81M   0% /run/user/1000
/dev/mapper/vg-data xfs        20G  176M   20G   1% /mnt

It now says 20GB.

Yum Cache Corruption

February 4, 2022 by Ulysses

If you’re getting a “HTTP Error 404 – Not Found” error when trying to run yum update, it could be a corrupted cache. Clear the cache on the system by running the following.

yum clean all
rm -rf /var/cache/yum/*

Run yum update again. The errors should be gone.