Add useful troubleshooting command/tools

1 files changed, 11 insertions, 75 deletions

diff --git a/linux/linux-troubleshoot.md b/linux/linux-troubleshoot.md
index b2b8850..cf8e6f6 100644
--- a/linux/linux-troubleshoot.md
+++ b/linux/linux-troubleshoot.md
@@ -1,75 +1,11 @@
-#### <u>Create/Resize a partition's (user/root) filesystem using LVM (Logical Volume Manager)</u>  
-  Useful if we want a flexible disk storage that we either need to create separate partitions on it or be able resize them on the fly.  
-  NOTE: LVM is mostly exclusive to linux, no offical support in most other OS's (Windows,FreeBSD..) and is redundent on filesystems like BTRFS since it has it's own Subvolume feature.
-  - LVM Concepts:  
-    - Physical Volumes occupy the "whole of" or a partition of the actual disks/drives that are phyically present.  
-    - Volume Groups are the overall collection of one or more physical volumes that encompass/split logical volumes.  
-    - Logical Volumes are the divided partitions of a volume group between potentially more than one disk/drive.  
-  ```bash  
-   ┌───────────────────────┐┌─────────────────────────────┐
-   │  Physical Hard Drive  ││    Physical Hard Drive      │
-   └───────────────────────┘└─────────────────────────────┘
-                            ┌───────────────────────┐
-                            │       Partition       │
-                            └───────────────────────┘
-   ┌───────────────────────┐┌───────────────────────┐
-   │    Physical Volume    ││    Physical Volume    │
-   └───────────────────────┘└───────────────────────┘
-   ┌────────────────────────────────────────────────┐
-   │                 Volume Group                   │
-   └────────────────────────────────────────────────┘
-   ┌───────────────────┐ ┌──────────────────────────┐
-   │  Logical Volume   │ │      Logical Volume      │
-   └───────────────────┘ └──────────────────────────┘
-   ┌───────────────────┐ ┌──────────────────────────┐
-   │    Filesystem     │ │        Filesystem        │
-   └───────────────────┘ └──────────────────────────┘
-  ```
-  1. First list/find out information about the partitions  
-  `$ df -h` # Displays amount of disk space on filesystems, "-h" in human readable form  
-  `$ lsblk` # List/find information about avaliable block devices/partitions
-  - Find info about VG(Volume Groups), PV(Physical Volumes) and LV(Logical Volumes):  
-      - hello  
-      `$ vgs` # Needs root privileges,  
-      - kk  
-      `$ lvs`
-      - Report information about Physical Volumes  
-      `$ pvs` # Needs root privileges,
-
-  2. Unmount the partition/filesystem making sure we are not on it  
-  NOTE: It is best not to be on the filesystem currently being managed although it's possible on EXT3 and EXT4 but BTRFS and ZFS need to be unmounted first (still safe to gather/list information on them though). So change to a different user and kill any processes of the target filesystem's user.  
-  `$ su root` # If going to change (extend/reduce) a user's filesystem  
-  `$ pkill <user>` # Make sure user's processes aren't running  
-  or  
-  `$ su <user>` # If going to change (extend/reduce) the root's filesystem  
-  then  
-  `umount /dev/path/<home_or_root>`  
-
-  3. Create/resize partitions  
-  - Create:
-    - Create the Logical Volume from existing free space within the Volume Group. The command below creates a LV with a size of 60GB from the VG called VG1 and LV name is Stuff
-    `$ lvcreate -L +60G --name Stuff VG1`
-    - Create a filesystem, creating the Logical Volume does not create the filesystem. The command below creates an EXT4 filesystem that fits the newly created Logical Volume.
-    `$ mkfs -t ext4 /dev/MyVG01/Stuff`
-Add a filesystem label
-
-Adding a filesystem label makes it easy to identify the filesystem later in case of a crash or other disk related problems.
-
-e2label /dev/MyVG01/Stuff Stuff
-  - Resize:  
-    - Reduce the Logical Volume:  
-    - Extend the Logical Volume:  
-
-Extend the Logical Volume (LV) from existing free space within the Volume Group. The command below expands the LV by 50GB. The Volume Group name is MyVG01 and the Logical Volume Name is Stuff.
-
-lvextend -L +50G /dev/MyVG01/Stuff
-  sudo lvextend -l 100%VG -r /dev/mapper/vg1-root
-  4. Mount the partition
-
-
-    ```
-    umount /dev/mapper/vg1-root
-    umount /dev/mapper/vg1-home
-    lvresize --resizefs -L -20G /dev/mapper/vg1-home
-    mount /dev/mapper/vg1-home
-    ```
+## Useful troubleshooting commands/tools
+#### Internet/network:  
+- ifconfig (install net-tools)  
+  - Manage interface configurations/parameters  
+  - Enable/disable a network interface  
+  - View all available interfaces, IP addresses, hardware addresses  
+  - Assign an IP address and netmask to a selected interface  
+- ip  
+  - Alternate to ifconfig, display network interfaces and configure network devices  
+  - Interact with layers of TCP/IP protocol (Data link layer and Network layer)  
+  - Can show and modify kernal routing tables (+/- ARP cache entries)