New answers tagged

0 votes

What is the fastest and safest RAID combination for SATA drives?

The Subject of File Server is deep. However very important aspects are easy to inform about. In the order of importance: For critical data you need server class cpu and ECC ram Against bit rot you ...
0 votes

Linux - RAM Disk as part of a Mirrored Logical Volume

The question is about RAM-disk like speed and persistence. This is possible as long as one allows asynchronous writes (keep the disk "catching up with writes"). As long as the application ...
  • 138
3 votes

Linux - RAM Disk as part of a Mirrored Logical Volume

Memcached, Redis You basically described Memcached, and somewhat Redis. Both are good at caching, Redis has better support for persistence. Note that you can only gain "all" the performance ...
4 votes

Linux - RAM Disk as part of a Mirrored Logical Volume

If you have this much free ram (that can hold most of these files and their metadata) chances are that they mostly reside in the RAM cache and your limiting factor is not reading, but writing them. If ...
  • 614
8 votes

Linux - RAM Disk as part of a Mirrored Logical Volume

First off, a RAM disk is almost never the correct answer on Linux. Because it is a block device, you end up with any read having to go through the block layer, and the filesystem, and the regular VFS ...
26 votes

Linux - RAM Disk as part of a Mirrored Logical Volume

To note, we would like to avoid merely RAM caching the files with the OS, but if we can get the same performance as a stand-alone RAM disk, that could work. We initially avoided this since often times ...
  • 422
7 votes

Linux - RAM Disk as part of a Mirrored Logical Volume

I have done something like this using AWS ephemeral disks, which are very fast but do not survive a power off/on cycle. We had a "seed-disk" which was a normal cheap EBS volume of GP2 (GP3 ...
  • 2,289
1 vote
Accepted

dell R730xd disk size less then total disk size after raid 0

In "pure" RAID mode, the smallest disk commands the maximum space that can be used for each disk. In other words, by mixing your 25 disks, you have a total of 25*300 GB == 7500 GB == 6985 ...
  • 44.4k
0 votes

KVM Host: Hardware RAID with cache + BBU vs. Linux Software RAID with LVM writeback cache and UPS

This is an old but still-relevant question. Linux Software RAID / mdadm RAID 5 A "plain" MD RAID5 of HDDs or consumer SSDs will be slow. To get good performance, one has to use powerloss-...
  • 44.4k
13 votes

Linux - RAM Disk as part of a Mirrored Logical Volume

This could be hacked together, but it is a bad idea and likely has multiple issues with reliability and maintainability. I think a RAID1 of RAMdisk and physical disk would be limited to the ...
7 votes

Linux - RAM Disk as part of a Mirrored Logical Volume

If you need persistence, a RAMDISK is not the correct solution. I strongly suggest to invest in a pair of fast (read: enterprise-grade, with powerloss protection) NVMe disk to put in a classical RAID1 ...
  • 44.4k
0 votes

Removed failed disk from

Your md3 array includes sda4, not sda1. If sda is gone, you can try to remove it from the array via mdadm -r /dev/md3 failed mdadm -r /dev/md3 detached but be sure it is the correct array (md3). If ...
  • 44.4k
1 vote

HP Raid Controller p420i 18TB disk support on DL380 Gen8?

Try to work with period-correct equipment. Gen8 HPE hardware is circa 2012-2015... So 10 year-old technology at this point. 18TB disks showed up around 2019/2020. You should focus on using more ...
  • 195k
3 votes

HP Raid Controller p420i 18TB disk support on DL380 Gen8?

Consider yourself lucky you came here at this stage, and that this didn't work. Firstly you're not supposed to run non-HPE disks on HPE disk controllers, I know some work but we've had a lot of people ...
  • 100k
2 votes

Which RAID is best for private use of NAS

Mathematically it is a terrible idea to use RAID 5 on any HDD that is larger than 2 TB - your chance of a read error WHILE reconstructing is too high. RAID 6 is the only answer here. That is the case ...
  • 51k
-1 votes

Which RAID is best for private use of NAS

Synology will handle the RAID and filesystem managements for you. They have a nice tool and documentations. If your NAS is your only backup and you don't need high performances, then RAID5 will give ...
1 vote

mdcheck hangs when attempting to stop check

It's probably this bug: https://lore.kernel.org/linux-raid/aa9567fd-38e1-7b9c-b3e1-dc2fdc055da5@molgen.mpg.de/ See also AskUbuntu: https://askubuntu.com/q/1428232/336440 If that is indeed your issue,...

Top 50 recent answers are included