When using FMADIO Packet capture system for analytics processing SSD resources can be split into Capture devices and Scratch disk space. In scratch disk space 1-16TB of SSD can be mounted as a general purpose file system used to store temporarily/intermediate network packet processing results.
The system should have scratch disks setup and visible on the GUI as follows, if this has not been configured contact support@fmad.io on how to configure
In the above example there are 2 disks SCR0 and SCR1 enabled for scratch disk these are seen on the file system as
Copy fmadio@fmadio20v3-287:~$ ls -al /opt/fmadio/disk/scr*
lrwxrwxrwx 1 root root 12 Jun 6 17:02 /opt/fmadio/disk/scr0 -> /dev/nvme2n1
lrwxrwxrwx 1 root root 12 Jun 6 17:02 /opt/fmadio/disk/scr1 -> /dev/nvme0n1
fmadio@fmadio20v3-287:~$ NOTE : the /dev/* mount point may change from time to time, please use the /opt/fmadio/disk/scr* path name for all operations.
NOTE : Any change to the scratch disk configuration it is recommend to run a Quick Format to ensure SSD and Capture disks configuration are consistent
Specifcying Sratch Disks
By default all SSD are specified are dedicated to capture. This is specified in the configuration file
Copy /opt/fmadio/etc/disk.lua Capture disks are specified here
Copy CacheDisk =
{
[ "S462NF0MA04379A" ] = "ssd0" ,
[ "S462NF0MA05134B" ] = "ssd1" ,
[ "S5JXNG0N108745Y" ] = "ssd2" ,
[ "S5JXNG0N108746D" ] = "ssd3" ,
} In the above example we have 4 x SSD for capture. To convert half to capture and half to scratch disk modify as follows
Copy CacheDisk =
{
[ "S462NF0MA04379A" ] = "ssd0" ,
[ "S462NF0MA05134B" ] = "ssd1" ,
}
,
ScratchDisk =
{
[ "S5JXNG0N108745Y" ] = "scr0" ,
[ "S5JXNG0N108746D" ] = "scr1" ,
} This is assigning the SSD Serial numbers to mount point /opt/fmadio/disk/scr0 and /opt/fmadio/disk/scr1. The actual Serial numbers for each system will be different, the mount point (scr0/scr1) is the same.
After updating confirm there are no syntax errors in the config file by running fmadiolua /opt/fmadio/etc/disk.lua as follows
Copy fmadio@fmadio20n40v3-363:~$ fmadiolua /opt/fmadio/etc/disk.lua
fmad fmadlua Jun 13 2021
calibrating...
0 : 2992970378 2.9930 cycles/nsec offset:7.030 Mhz
Cycles/Sec 2992970378.0000 Std: 0 cycle std( 0.00000000) Target:3.00 Ghz
argv fmadiolua
failed to open self? [fmadiolua]
loading filename [/opt/fmadio/etc/disk.lua]
done 0.000038Sec 0.000001Min
fmadio@fmadio20n40v3-363:~$ Output as above shows correctly formatted file. Output per below shows configuration file with a syntax error (line 30 has some incorrect formatting)
Copy fmadio@fmadio20n40v3-363:~$ fmadiolua /opt/fmadio/etc/disk.lua
fmad fmadlua Jun 13 2021
calibrating...
0 : 2992970368 2.9930 cycles/nsec offset:7.030 Mhz
Cycles/Sec 2992970368.0000 Std: 0 cycle std( 0.00000000) Target:3.00 Ghz
argv fmadiolua
failed to open self? [fmadiolua]
loading filename [/opt/fmadio/etc/disk.lua]
load status: 3 0
/opt/fmadio/etc/disk.lua:30: '}' expected (to close '{' at line 2) near 'ScratchDisk'
fmadio@fmadio20n40v3-363:~$ After confirming the configuration file syntax is correct, reboot the system. The mount points scr0 and scr1 should be visible as shown below.
Copy fmadio@fmadio20n40v3-363:~$ ls -al /opt/fmadio/disk/scr*
lrwxrwxrwx 1 root root 12 Jun 6 17:02 /opt/fmadio/disk/scr0 -> /dev/nvme2n1
lrwxrwxrwx 1 root root 12 Jun 6 17:02 /opt/fmadio/disk/scr1 -> /dev/nvme0n1
fmadio@fmadio20n40v3-363:~$ Creating RAID0 partition
After /opt/fmadio/disk/scr[0-1] have been created. Next is creating a /dev/md1 RAID0 partition as follows
Copy fmadio@fmadio20v3-287:~$ sudo mdadm --create /dev/md1 --force --level=raid0 --raid-devices=2 /opt/fmadio/disk/scr0 /opt/fmadio/disk/scr1
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md1 started.
fmadio@fmadio20v3-287:~$ This creates a /dev/md1 partition as shown with lsblk command. Can see the /dev/md1 device
Copy fmadio@fmadio20v3-287:~$ lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sdd 8:48 0 3.7T 0 disk
sdb 8:16 0 3.7T 0 disk
nvme2n1 259:0 0 447.1G 0 disk
`-md1 9:1 0 894G 0 raid0
nvme1n1 259:3 0 477G 0 disk
sde 8:64 0 3.7T 0 disk
sdc 8:32 0 3.7T 0 disk
sda 8:0 0 238.5G 0 disk
|-sda2 8:2 0 223.6G 0 part /mnt/store0
`-sda1 8:1 0 14.9G 0 part /mnt/sda1
nvme0n1 259:1 0 447.1G 0 disk
`-md1 9:1 0 894G 0 raid0
nvme3n1 259:2 0 477G 0 disk
fmadio@fmadio20v3-287:~$ More detail via the mdadm --detail command
Copy fmadio@fmadio20v3-287:~$ sudo mdadm --detail /dev/md1
/dev/md1:
Version : 1.2
Creation Time : Sun Jun 6 17:43:12 2021
Raid Level : raid0
Array Size : 937440256 (894.01 GiB 959.94 GB)
Raid Devices : 2
Total Devices : 2
Persistence : Superblock is persistent
Update Time : Sun Jun 6 17:43:12 2021
State : clean
Active Devices : 2
Working Devices : 2
Failed Devices : 0
Spare Devices : 0
Chunk Size : 512K
Name : fmadio20v3-287:1 (local to host fmadio20v3-287)
UUID : 06234ac8:694ae295:3659e4fc:b59a7d55
Events : 0
Number Major Minor RaidDevice State
0 259 0 0 active sync /dev/nvme2n1
1 259 1 1 active sync /dev/nvme0n1
fmadio@fmadio20v3-287:~$ Create EXT4 Filesystem
The block device /dev/md1 is block level only, it contains no mountable file system. Next create btrfs filesystem on the device as follows
Copy fmadio@fmadio20v3-287:~$ sudo mkfs.ext4 /dev/md1
mke2fs 1.42.7 (21-Jan-2013)
Discarding device blocks: done
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=128 blocks, Stripe width=256 blocks
125009920 inodes, 500036608 blocks
25001830 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=4294967296
15260 block groups
32768 blocks per group, 32768 fragments per group
8192 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000, 7962624, 11239424, 20480000, 23887872, 71663616, 78675968,
102400000, 214990848
Allocating group tables: done
Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done
fmadio@fmadio20v3-287:~$ Mount the Scratch Filesystem
By default FMADIO Packet Capture systems at boot time will start the RAID0 partition and mount /dev/md1 Scratch disk to /mnt/store1
If it fails to mount, please issue the following command
Copy fmadio@fmadio20v3-287:~$ sudo mount -t ext4 /dev/md1 /mnt/store1
fmadio@fmadio20v3-287:~$ 
