On 10/15/18 6:39 AM, Larry Linder wrote: > When you look at the /dev/disk and the directories there is no occurance > of "sde" > > We tried to modify "fstab" manuall but the device code - decoding scheme > didn't work. System booted to "rescue". > > There are a number of problems with the GigaBit MB and one has to do > with the serial communication. > > I looked into the bios and all 4 WD disks are present. Disk 5 as "sde" > is not seen there. We tried moving disks around and the same result so > its not a disk problem. > These are all WD disks > > However we have noticed that when you count up the devices to be mounted > in "fstab" there are 16. A number of the mounts are due to the user and > SL OS. > > On this server we will stick with xt4 for the time being. > > We have investigated a Port Expansion board to allow us to use more > physical disks but when you peek under the covers and look how they work > the performance penality is not worth the trouble. > > Larry Linder > > On Sat, 2018-10-13 at 09:55 -0700, Bruce Ferrell wrote: >> My one and only question is, do you see the device for sde, in any >> form (/dev/sdeX, /dev/disk/by-*, etc) present in /etc/fstab with the >> proper mount point(s)? >> >> It really doesn't matter WHAT the device tech is. /etc/fstab just >> tells the OS where to put the device into the filesystem... Or it did >> before systemd got into the mix. >> >> Just for grins and giggles, I'd put sde (and it's correct >> partition/mount point) into fstab and reboot during a maintenance >> window. >> >> if that fails, I'd be taking a hard look at systemd and the units that >> took over disk mounting. Systemd is why I'm still running SL 6.x >> >> Also, if you hot swapped the drive, the kernel has a nasty habit of >> assigning a new device name. What WAS sde becomes sdf until the next >> reboot... But fstab and systemd just don't get that. Look for >> anomalies. disk devices that you don't recognize in fstab or the >> systemd configs. >> >> >> On 10/13/18 7:20 AM, Larry Linder wrote: >> >>> The problem is not associated with the file system. >>> We have a newer system with SL 7.5 and xfs and we have the same problem. >>> >>> I omited a lot of directories because of time and importance. fstab is >>> what is mounted and used by OS. >>> >>> The fstab was copied exactly as SL 7.5 built it. It does not give you a >>> clue as to what the directories are and it shouldn't. >>> >>> The point is that I would like to use more pysical drives on this system >>> but because of MB or OS the last physical disk is not seen, which is >>> "sde". One of older SCSI sysems had 31 disks attached to it. >>> >>> The Bios does sees 1 SSD, 4 WesternDigital drives and 1 dvd. >>> SSD sda >>> WD sdb >>> WD sdc >>> WD sdd >>> WD sde is missing from "fstab" and not mounted. >>> plextor dvd >>> >>> We tried a nanual mount and it works but when you reboot it is gone >>> becasuse it not in "fstab". >>> >>> Why so many disks: >>> Two of these disks are used for back up of users on the server. Twice a >>> day @ 12:30 and at 0:30 each day. These are also in sync with two disks >>> that are at another physical location. Using "rsync" you have to be >>> carefull or it can be an eternal garbage colledtor. This is off topic. >>> >>> A disk has a finite life so every 6 mo. We rotate in a new disk and >>> toss the oldest one. It takes two and 1/2 years to cycle threw the >>> pack. >>> This scheme has worked for us for the last 20 years. We have never had >>> a server die on us. We have used Sl Linux form version 4 to current and >>> before that RH 7->9 and BSD 4.3. >>> >>> We really do not have a performance problem even on long 3d renderings- >>> The slowest thing in the room is the speed one can type or point. >>> Models, simulations, drawings are done before you can reach for your >>> cup. >>> >>> Thank You >>> Larry Linder >>> >>> >>> On Fri, 2018-10-12 at 23:07 -0700, Bruce Ferrell wrote: >>>> On 10/12/18 8:09 PM, ~Stack~ wrote: >>>>> On 10/12/2018 07:35 PM, Nico Kadel-Garcia wrote: >>>>> [snip] >>>>>> On SL 7? Why? Is there any reason not to use xfs? I've appreciated the >>>>>> ext filesystems, I've known its original author for decades. (He was >>>>>> my little brother in my fraternity!) But there's not a compelling >>>>>> reason to use it in recent SL releases. >>>>> Sure there is. Anyone who has to mange fluctuating disks in an LVM knows >>>>> precisely why you avoid XFS - Shrink an XFS formated LVM partition. Oh, >>>>> wait. You can't. ;-) >>>>> >>>>> My server with EXT4 will be back on line with adjusted filesystem sizes >>>>> before the XFS partition has even finished backing up! It is a trivial, >>>>> well-documented, and quick process to adjust an ext4 file-system. >>>>> >>>>> Granted, I'm in a world where people can't seem to judge how they are >>>>> going to use the space on their server and frequently have to come to me >>>>> needing help because they did something silly like allocate 50G to /opt >>>>> and 1G to /var. *rolls eyes* (sadly that was a true event.) Adjusting >>>>> filesystems for others happens far too frequently for me. At least it is >>>>> easy for the EXT4 crowd. >>>>> >>>>> Also, I can't think of a single compelling reason to use XFS over EXT4. >>>>> Supposedly XFS is great for large files of 30+ Gb, but I can promise you >>>>> that most of the servers and desktops I support have easily 95% of their >>>>> files under 100M (and I would guess ~70% are under 1M). I know this, >>>>> because I help the backup team on occasion. I've seen the histograms of >>>>> file size distributions. >>>>> >>>>> For all the arguments of performance, well I wouldn't use either XFS or >>>>> EXT4. I use ZFS and Ceph on the systems I want performance out of. >>>>> >>>>> Lastly, (I know - single data point) I almost never get the "help my >>>>> file system is corrupted" from the EXT4 crowd but I've long stopped >>>>> counting how many times I've heard XFS eating files. And the few times >>>>> it is EXT4 I don't worry because the tools for recovery are long and >>>>> well tested. The best that can be said for XFS recovery tools is "Well, >>>>> they are better now then they were." >>>>> >>>>> To me, it still boggles my mind why it is the default FS in the EL world. >>>>> >>>>> But that's me. :-) >>>>> >>>>> ~Stack~ >>>>> >>>> The one thing I'd offer you in terms of EXT4 vs XFS.... Do NOT have a system crash on very large filesystems (> than 1TB) with EXT4. >>>> >>>> It will take days to fsck completely. Trust me on this. I did it (5.5TB RAID6)... and then converted to XFS. Been running well for 3 years now. One other thing to look at is the kernel ring buffer with the dmesg command. When you pull and re-insert the drive, you'll see messages there from udev and the kernel detecting the drive and assigning device names The fact that you see no sde in /dev/disk (and sub dirs) is an excellent indication the drive got assigned a new ID by udev.