Allen Berezovsky / Getty Images. Common is well known as a conscious rapper who advocates for love, peace, and all things pure. So it makes sense that Common lives a drug-free life. Despite being connected to the mainstream party culture, Common parties clean. The Oscar winner works out regularly and eats healthfully.
All drives are going to trip at some point or other. Next time your Unidrive is throwing an error code, the following information may help.
- Does asap usually use auto tune live? Haven't watched much of his shows. NF: CLOUDS (THE MIXTAPE) NF Real Music/Virgin: 61,541.
- Auto-Tune the News was the brainchild of the Brooklyn band The Gregory Brothers. Auto-Tune the News took real video clips of politicians in their natural element and digitally manipulated them so they break into song. When the domain registration of Auto-Tune the News expired the site disappeared from the web.
- Deep, Dark, Twisted. Stargaze is our most aberrant free vocal preset yet. Hard smashing limiters combine with soul crushing saturators to turn your vocals into that bold authority you need to command your audiences attention. Empower humanized super-rigid Autotune settings, drowning delays and endless reverbs to bless your audience with your angelic Stargaze voice. If you're searching for an.
[table id=12 /]
Repair
If you have an AC / DC drive module breakdown or stability issue our engineers are able to analyse the whole machine to identify where the control issues lie. Our extensive experience in retrofit and new projects means we have the knowledge to look deep into the control system where we commonly find the peripheral devices are faulty rather than the drive module.
Our team of engineers are able to offer on site service and breakdown support throughout the UK to get you up and running again quickly.
If you have a faulty drive but don’t require on site support, Drives and Automation are able to repair them at our repair centre in Telford. Our trained engineers will strip down your drive and send you a repair quotation. If you are happy to proceed we will repair the drive, clean it and load test it before returning it to you. Fast turnarounds are usually no problem!
[maxbutton id=”7″]
Replace
The Unidrive SP is now a superceded product and is in it’s maintenance period. Volume production of these products has now ceased, but manufacturer contractual obligations regarding warranty, service and repairs will continue. The maintenance period is expected to last up to ten years subject to raw material and component availability and will end in 2027 when no further manufacturer support will be available. Drives and Automation are able to supply refurbished units for certain models, simply contact us with details of your existing Unidrive SP and we will see if we can offer you a replacement.
[maxbutton id=”8″]
Upgrade
In 2013, the Unidrive SP and Commander SK were replaced by a new range of industrial AC drives called Unidrive M. Unidrive M’s design is based on the success and popularity of Unidrive SP and Commander SK, and incorporates market-leading technologies. If you are wanting to upgrade your obsolete Unidrive SP to an M Series Drive, use our quick reference guide to choose the right replacement Drive for your application:
[maxbutton id=”9″]
From Wikipedia:
- Network File System (NFS) is a distributed file system protocol originally developed by Sun Microsystems in 1984, allowing a user on a client computer to access files over a network in a manner similar to how local storage is accessed.
- NFS is not encrypted. Tunnel NFS through an encrypted protocol like Kerberos or (secure) VPN when dealing with sensitive data.
- Unlike Samba, NFS does not have any user authentication by default, client access is restricted by their IP-address/hostname.
- NFS expects the user and/or user group ID's are the same on both the client and server. Enable NFSv4 idmapping or overrule the UID/GID manually by using
anonuid
/anongid
together withall_squash
in/etc/exports
.
Installation
Both client and server only require the installation of the nfs-utils package.
It is highly recommended to use a time synchronization daemon to keep client/server clocks in sync. Without accurate clocks on all nodes, NFS can introduce unwanted delays.
Configuration
Server
Global configuration options are set in /etc/nfs.conf
. Users of simple configurations should not need to edit this file.
The NFS server needs a list of exports (see exports(5) for details) which are defined in /etc/exports
or /etc/exports.d/*.exports
. These shares are relative to the so-called NFS root. A good security practice is to define a NFS root in a discrete directory tree which will keep users limited to that mount point. Bind mounts are used to link the share mount point to the actual directory elsewhere on the filesystem.
Consider this following example wherein:
- The NFS root is
/srv/nfs
. - The export is
/srv/nfs/music
via a bind mount to the actual target/mnt/music
.
To make the bind mount persistent across reboots, add it to fstab:
Add directories to be shared and limit them to a range of addresses via a CIDR or hostname(s) of client machines that will be allowed to mount them in /etc/exports
, e.g.:
fsid=0
, other directories must be below it. The rootdir
option in the /etc/nfs.conf
file has no effect on this.- The
crossmnt
option makes it possible for clients to access all filesystems mounted on a filesystem marked withcrossmnt
and clients will not be required to mount every child export separately. Note this may not be desirable if a child is shared with a different range of addresses. - Instead of
crossmnt
, one can also use thenohide
option on child exports so that they can be automatically mounted when a client mounts the root export. Being different fromcrossmnt
,nohide
still respects address ranges of child exports. - Use an asterisk (*) to allow access from any interface.
It should be noted that modifying /etc/exports
while the server is running will require a re-export for changes to take effect:
To view the current loaded exports state in more detail, use:
For more information about all available options see exports(5).
fsid=1
option is required.Starting the server
Start and enablenfs-server.service
.
rpc-gssd.service
) will wait until the random number generator pool is sufficiently initialized possibly delaying the boot process. This is particularly prevalent on headless servers. It is highly recommended to populate the entropy pool using a utility such as Rng-tools (if TPM is supported) or Haveged in these scenarios.zfs-share.service
. Without this, ZFS shares will no longer be exported after a reboot. See ZFS#NFS.Restricting NFS to interfaces/IPs
By default, starting nfs-server.service
will listen for connections on all network interfaces, regardless of /etc/exports
. This can be changed by defining which IPs and/or hostnames to listen on.
Restartnfs-server.service
to apply the changes immediately.
Firewall configuration
To enable access through a firewall, TCP and UDP ports 111
, 2049
, and 20048
may need to be opened when using the default configuration; use rpcinfo -p
to examine the exact ports in use on the server:
When using NFSv4, make sure TCP port 2049
is open. No other port opening should be required:
When using an older NFS version, make sure other ports are open:
To have this configuration load on every system start, edit /etc/iptables/iptables.rules
to include the following lines:
The previous commands can be saved by executing:
If using NFSv3 and the above listed static ports for rpc.statd
and lockd
the following ports may also need to be added to the configuration:
To apply changes, Restartiptables.service
.
Enabling NFSv4 idmapping
This article or section needs expansion.
- NFSv4 idmapping does not work with the default
sec=sys
mount option. [1] - NFSv4 idmapping needs to be enabled on both the client and server.
- Another option is to make sure the user and group IDs (UID and GID) match on both the client and server.
- Enabling/starting
nfs-idmapd.service
should not be needed as it has been replaced with a new id mapper:
The NFSv4 protocol represents the local system's UID and GID values on the wire as strings of the form user@domain
. The process of translating from UID to string and string to UID is referred to as ID mapping. See nfsidmap(8) for details.
Even though idmapd may be running, it may not be fully enabled. If /sys/module/nfs/parameters/nfs4_disable_idmapping
or /sys/module/nfsd/parameters/nfs4_disable_idmapping
returns Y
on a client/server, enable it by:
nfs4
and nfsd
need to be loaded (respectively) for the following paths to be available.On the client:
On the server:
Set as module option to make this change permanent, i.e.:
To fully use idmapping, make sure the domain is configured in /etc/idmapd.conf
on both the server and the client:
See [2] for details.
Client
Users intending to use NFS4 with Kerberos need to start and enablenfs-client.target
.
Manual mounting
For NFSv3 use this command to show the server's exported file systems:
For NFSv4 mount the root NFS directory and look around for available mounts:
Then mount omitting the server's NFS export root:
If mount fails try including the server's export root (required for Debian/RHEL/SLES, some distributions need -t nfs4
instead of -t nfs
):
Mount using /etc/fstab
Using fstab is useful for a server which is always on, and the NFS shares are available whenever the client boots up. Edit /etc/fstab
file, and add an appropriate line reflecting the setup. Again, the server's NFS export root is omitted.
Some additional mount options to consider:
- rsize and wsize
- The
rsize
value is the number of bytes used when reading from the server. Thewsize
value is the number of bytes used when writing to the server. By default, if these options are not specified, the client and server negotiate the largest values they can both support (see nfs(5) for details). After changing these values, it is recommended to test the performance (see #Performance tuning).
- soft or hard
- Determines the recovery behaviour of the NFS client after an NFS request times out. If neither option is specified (or if the
hard
option is specified), NFS requests are retried indefinitely. If thesoft
option is specified, then the NFS client fails a NFS request after retrans retransmissions have been sent, causing the NFS client to return an error to the calling application.
soft
timeout can cause silent data corruption in certain cases. As such, use the soft
option only when client responsiveness is more important than data integrity. Using NFS over TCP or increasing the value of the retrans
option may mitigate some of the risks of using the soft
option.- timeo
- The
timeo
value is the amount of time, in tenths of a second, to wait before resending a transmission after an RPC timeout. The default value for NFS over TCP is 600 (60 seconds). After the first timeout, the timeout value is doubled for each retry for a maximum of 60 seconds or until a major timeout occurs. If connecting to a slow server or over a busy network, better stability can be achieved by increasing this timeout value.
- retrans
- The number of times the NFS client retries a request before it attempts further recovery action. If the
retrans
option is not specified, the NFS client tries each request three times. The NFS client generates a 'server not responding' message after retrans retries, then attempts further recovery (depending on whether the hard mount option is in effect).
- _netdev
- The
_netdev
option tells the system to wait until the network is up before trying to mount the share - systemd assumes this for NFS.
fs_passno
) to a nonzero value may lead to unexpected behaviour, e.g. hangs when the systemd automount waits for a check which will never happen.Mount using /etc/fstab with systemd
Another method is using the x-systemd.automount option which mounts the filesystem upon access:
To make systemd aware of the changes to fstab, reload systemd and restart remote-fs.target
[3].
The factual accuracy of this article or section is disputed.
- The
noauto
mount option will not mount the NFS share until it is accessed: useauto
for it to be available immediately.
If experiencing any issues with the mount failing due to the network not being up/available, enableNetworkManager-wait-online.service
. It will ensure thatnetwork.target
has all the links available prior to being active. - The
users
mount option would allow user mounts, but be aware it implies further options asnoexec
for example. - The
x-systemd.idle-timeout=1min
option will unmount the NFS share automatically after 1 minute of non-use. Good for laptops which might suddenly disconnect from the network. - If shutdown/reboot holds too long because of NFS, enable
NetworkManager-wait-online.service
to ensure that NetworkManager is not exited before the NFS volumes are unmounted. - Do not add the
x-systemd.requires=network-online.target
mount option as this can lead to ordering cycles within systemd [4]. systemd adds thenetwork-online.target
dependency to the unit for_netdev
mount automatically. - Using the
nocto
option may improve performance for read-only mounts, but should be used only if the data on the server changes only occasionally.
As systemd unit
Create a new .mount
file inside /etc/systemd/system
, e.g. mnt-myshare.mount
. See systemd.mount(5) for details.
mnt-myshare.mount
can only be used if you are going to mount the share under /mnt/myshare
. Otherwise the following error might occur: systemd[1]: mnt-myshare.mount: Where= setting does not match unit name. Refusing.
.What=
path to share
Where=
path to mount the share
Options=
share mounting options
- Network mount units automatically acquire
After
dependencies onremote-fs-pre.target
,network.target
andnetwork-online.target
, and gain aBefore
dependency onremote-fs.target
unlessnofail
mount option is set. Towards the latter aWants
unit is added as well. - Append
noauto
toOptions
preventing automatically mount during boot (unless it is pulled in by some other unit). - If you want to use a hostname for the server you want to share (instead of an IP address), add
nss-lookup.target
toAfter
. This might avoid mount errors at boot time that do not arise when testing the unit.
ForceUnmount=true
to [Mount]
, allowing the share to be (force-)unmounted.To use mnt-myshare.mount
, start the unit and enable it to run on system boot.
automount
To automatically mount a share, one may use the following automount unit:
Disable/stop the mnt-myshare.mount
unit, and enable/startmnt-myshare.automount
to automount the share when the mount path is being accessed.
TimeoutIdleSec
to enable auto unmount. See systemd.automount(5) for details.Mount using autofs
Does Nf Use Auto Tunes
Using autofs is useful when multiple machines want to connect via NFS; they could both be clients as well as servers. The reason this method is preferable over the earlier one is that if the server is switched off, the client will not throw errors about being unable to find NFS shares. See autofs#NFS network mounts for details.
Tips and tricks
Performance tuning
When using NFS on a network with a significant number of clients one may increase the default NFS threads from 8 to 16 or even a higher, depending on the server/network requirements:
It may be necessary to tune the rsize
and wsize
mount options to meet the requirements of the network configuration.
In recent linux kernels (>2.6.18) the size of I/O operations allowed by the NFS server (default max block size) varies depending on RAM size, with a maximum of 1M (1048576 bytes), the max block size of the server will be used even if nfs clients requires bigger rsize
and wsize
. See https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/5/html/5.8_Technical_Notes/Known_Issues-kernel.htmlIt is possible to change the default max block size allowed by the server by writing to the /proc/fs/nfsd/max_block_size
before starting nfsd. For example, the following command restores the previous default iosize of 32k:
To make the change permanent, create a systemd-tmpfile:
To mount with the increased rsize
and wsize
mount options:
Furthermore, despite the violation of NFS protocol, setting async
instead of sync
or sync,no_wdelay
may potentially achieve a significant performance gain especially on spinning disks. Configure exports with this option and then execute exportfs -arv
to apply.
async
comes with a risk of possible data loss or corruption if the server crashes or restarts uncleanly.Automatic mount handling
This trick is useful for NFS-shares on a wireless network and/or on a network that may be unreliable. If the NFS host becomes unreachable, the NFS share will be unmounted to hopefully prevent system hangs when using the hard
mount option [5].
Make sure that the NFS mount points are correctly indicated in fstab:
Note:- Use hostnames in fstab for this to work, not IP addresses.
- In order to mount NFS shares with non-root users the
users
option has to be added. - The
noauto
mount option tells systemd to not automatically mount the shares at boot, otherwise this may cause the boot process to stall.
Create the auto_share
script that will be used by cron or systemd/Timers to use ICMP ping to check if the NFS host is reachable:
with:
in theauto_share
script above.Make sure the script is executable:
Does Nf Use Auto Tune
Next check configure the script to run every X, in the examples below this is every minute.
Does Nf Use Auto Tuner
Cron
systemd/Timers
Finally, enable and startauto_share.timer
.
Using a NetworkManager dispatcher
NetworkManager can also be configured to run a script on network status change.
The easiest method for mount shares on network status change is to symlink the auto_share
script:
However, in that particular case unmounting will happen only after the network connection has already been disabled, which is unclean and may result in effects like freezing of KDE Plasma applets.
The following script safely unmounts the NFS shares before the relevant network connection is disabled by listening for the pre-down
and vpn-pre-down
events, make the script is executable:
noauto
option, remove this mount option or use auto
to allow the dispatcher to manage these mounts.Create a symlink inside /etc/NetworkManager/dispatcher.d/pre-down
to catch the pre-down
events:
Troubleshooting
There is a dedicated article NFS/Troubleshooting.
See also
- See also Avahi, a Zeroconf implementation which allows automatic discovery of NFS shares.
- HOWTO: Diskless network boot NFS root
- Microsoft Services for Unix NFS Client info[dead link 2021-05-17 ⓘ]