Mount filesystems
Discover the two modes for mounting a filesystem on a cluster server: persistent mount mode (stateful) and stateless mount mode. You can also use fstab or autofs for mounting.
Overview
There are two modes available for mounting a filesystem in a cluster server:
Persistent mount mode (stateful): This mode involves configuring a client to join the cluster before running the mount command.
Stateless mount mode: This mode simplifies and improves client management by eliminating the need for the Adding Clients process.
If you need to mount filesystems from multiple clusters on a single client, refer to the relevant topic for detailed instructions.
In addition, you can mount a filesystem using fstab or autofs.
Related topics
Mount a filesystem using the persistent mount mode
Mount a filesystem using the stateless mount mode
Mount a filesystem using fstab
Mount a filesystem using autofs
Mount filesystems from multiple clusters on a single client
Mount a filesystem using the persistent mount mode
To mount a WEKA filesystem persistently, follow these steps:
Install the WEKA client: Ensure the WEKA client is installed, configured, and connected to your WEKA cluster. See Add clients to an on-premises WEKA cluster.
Identify the filesystem: Determine the name of the filesystem you want to mount. For this example, we use a filesystem named
demo
.Create a mount point: SSH into one of your cluster servers and create a directory to serve as the mount point for the filesystem:
Mount the filesystem: As the root user, run the following command to mount the filesystem:
General command structure: The general syntax for mounting a WEKA filesystem is:
Replace <fs-name>
with the name of your filesystem and <mount-point>
with the directory you created for mounting.
Read and write cache modes: When mounting a filesystem, you can choose between two cache modes: read cache and write cache. Each mode offers distinct advantages depending on your use case. For detailed descriptions of these modes, refer to the following links:
Mount a filesystem using the stateless mount mode
The stateless mount mode simplifies client management by deferring the joining of the cluster until the mount operation is performed. This approach is particularly beneficial in environments like AWS, where clients frequently join and leave the cluster.
Key benefits
Simplified client management: Eliminates the need for tedious client management procedures.
Unified security: Consolidates all security aspects within the mount command, removing the need to manage separate credentials for cluster join and mount.
Prerequisites
WEKA Agent: Ensure the WEKA agent is installed on your client to utilize the stateless mount mode. See Add clients to an on-premises WEKA cluster.
Mount a filesystem
Once the WEKA agent is installed, you can create and configure mounts using the mount command. To mount a filesystem:
Create and configure mounts: Use the
mount
command to create and configure the mounts. See Mount command options.Unmounting: Remove existing mounts from the cluster using the
unmount
command.
Authentication
To restrict mounting to only WEKA authenticated users, set the --auth-required
flag to yes
for the filesystem. For more information, refer to Mount authentication for organization filesystems.
Set a stateless client with restricted operations on an Isolated port
To restrict a stateless client's operations to only the essential APIs for mounting and unmounting, connect to WEKA clusters through TCP base port + 3 (for example, 14003). This configuration enables operational segregation between client and backend control plane requests.
Mount with restricted options
When mounting with the restricted option, the logged-in user's privileges are set to regular user privileges, regardless of the user's role.
Install the WEKA agent
To install a WEKA agent on a client, run one of the following commands as root
on the client:
For a non-restricted client:
For a restricted client:
The -k
flag instructs the curl
command to bypass SSL certificate verification.
After running the appropriate command, the agent is installed on the client.
Run the mount command
Command: mount -t wekafs
Command syntax
Use one of the following command lines to invoke the mount command. The delimiter between the server and filesystem can be either :/
or /
:
Example: Mount for a restricted stateless client on an isolated port
This setup ensures that the stateless client operates with restricted privileges, maintaining a secure and controlled environment for mounting and unmounting operations on an isolated port.
Parameters
Name | Value |
---|---|
| See Additional Mount Options below. |
| IP/hostname of a backend container. Mandatory. |
| Filesystem name. Mandatory. |
| Path to mount on the local server. Mandatory. |
Mount command options
Each mount option can be passed by an individual -o
flag to mount.
For all clients types
Option | Description | Default | Remount Supported |
---|---|---|---|
| Set the mount mode to read from the cache. This action automatically turns off the Note: The SMB share mount mode is always | No | Yes |
| Set the mount mode to write to the cache. | Yes | Yes |
| Set the mount mode to directly read from and write to storage, avoiding the cache. This action automatically turns off both the Note: Enabling this option could impact performance. Use it carefully. If you’re unsure, contact the Customer Success Team. Do not use this option for SMB shares. | No | Yes |
| The time in milliseconds after which the system refreshes the metadata cached entry. This refresh informs the WEKA client about metadata changes performed by other clients. | 1000 | Yes |
| Each time a file or directory lookup fails, the local entry cache creates an entry specifying that the file or directory does not exist. This entry is refreshed after the specified time (number in milliseconds), allowing the WEKA client to use files or directories created by other clients. | 0 | Yes |
| Mount filesystem as read-only. | No | Yes |
| Mount filesystem as read-write. | Yes | Yes |
| The inode size in bits may be required for 32-bit applications.
Possible values: | Auto | No |
| Write debug logs to the console. | No | Yes |
| Don't show any logs to console. | No | Yes |
| Can be defined per mount. Setting POSIX ACLs can change the effective group permissions (via the | No | No |
| No | Yes | |
| Do not update inode access times. | No | Yes |
| Always update inode access times. | No | Yes |
| Update inode access times only on modification or change, or if inode has been accessed and | Yes | Yes |
| The time (number in seconds) to wait since an inode has been accessed (not modified) before updating the access time. 0 means never update the access time on access only. This option is relevant only if the | 0 (infinite) | Yes |
| Do not take | No | Yes |
| Do not interpret character or block special devices. | No | Yes |
| Do not allow direct execution of any binaries. | No | Yes |
| File creation mask. A numeric (octal) notation of POSIX permissions.
Newly created file permissions are masked with the creation mask. For example, if a user creates a file with permissions=777 but the First, the | 0777 | Yes |
| Directory creation mask. A numeric (octal) notation of POSIX permissions.
Newly created directory permissions are masked with the creation mask. For example, if a user creates a directory with permissions=777 but the First, the | 0777 | Yes |
| Force file mode. A numeric (octal) notation of POSIX permissions.
Newly created file permissions are logically OR'ed with the mode.
For example, if a user creates a file with permissions 770 but the First, the | 0 | Yes |
| Force directory mode. A numeric (octal) notation of POSIX permissions.
Newly created directory permissions are logically OR'ed with the mode. For example, if a user creates a directory with permissions 770 but the First, the | 0 | Yes |
| This option ensures that all data for a file is written to the server when the file is closed. This means that changes made to the file by the client are immediately written to the server's disk upon close, which can provide greater data consistency and reliability.
It simulates the open-to-close semantics of NFS when working with | No | Yes |
| This option disables the | No | Yes |
Remount of general options
You can remount using the mount options marked as Remount Supported
in the above table (mount -o remount)
.
When a mount option has been explicitly changed, you must set it again in the remount operation to ensure it retains its value. For example, if you mount with ro
, a remount without it changes the mount option to the default rw
. If you mount with rw
, it is not required to re-specify the mount option because this is the default.
Additional mount options using the stateless clients feature
Option | Description | Default | Remount Supported |
---|---|---|---|
| The memory size in MiB the client can use for hugepages. |
| Yes |
| The number of frontend cores to allocate for the client. You can specify If none are specified, the client is configured with 1 core. If you specify 0 then you must use |
| No |
| Specify explicit cores to be used by the WekaFS client. Multiple cores can be specified. Core 0 is not allowed. | No | |
| This option must be specified for on-premises installation and must not be specified for AWS installations. For more details, see Advanced network configuration by mount option. | No | |
| The time in seconds without connectivity, after which the client is removed from the cluster.
Minimum value: |
| Yes |
| Traces capacity limit in MB. Minimum value: 512 MB. | No | |
| Controls the page allocation algorithm to reserve hugepages.
Possible values:
|
| Yes |
| The readahead size in KB per mount. A higher readahead is better for sequential reads of large files. |
| Yes |
| The path to the mount authentication token (per mount). |
| No |
| Determine whether DPDK networking dedicates a core ( |
| No |
| Preferred requests rate for QoS in megabytes per second. |
| Yes |
| Maximum requests rate for QoS in megabytes per second. This option allows bursting above the specified limit but aims to keep this limit on average. The cluster admin can set the default value. See Set mount option default values. |
| Yes |
| Maximum number of IO operations a client can perform per second. Set a limit to a client or clients to prevent starvation from the rest of the clients. (Do not set this option for mounting from a backend.) |
| Yes |
| The timeout, in seconds, for establishing a connection to a single server. |
| Yes |
| The timeout, in seconds, waiting for the response from a single server. |
| Yes |
| The timeout, in seconds, for the client container to join the Weka cluster. |
| Yes |
| The base memory in MB to allocate for DPDK. Set this option when mounting to a WEKA cluster on GCP.
Example: |
| Yes |
| The WEKA client version to run. | The cluster version | No |
| Restricts a stateless client’s operations to only the essential APIs for mounting and unmounting operations. | No |
These parameters, if not stated otherwise, are only effective on the first mount command for each client.
By default, the command selects the optimal core allocation for WEKA. If necessary, multiple core
parameters can be used to allocate specific cores to the WekaFS client. For example, mount -t wekafs -o core=2 -o core=4 -o net=ib0 backend-server-0/my_fs /mnt/weka
Example: On-Premise Installations
mount -t wekafs -o num_cores=1 -o net=ib0 backend-server-0/my_fs /mnt/weka
Running this command on a server installed with the Weka agent downloads the appropriate WEKA version from the backend-server-0
and creates a WEKA container that allocates a single core and a named network interface (ib0
). Then it joins the cluster that backend-server-0
is part of and mounts the filesystem my_fs
on /mnt/weka.
mount -t wekafs -o num_cores=0 -o net=udp backend-server-0/my_fs /mnt/weka
Running this command uses UDP mode (usually selected when the use of DPDK is not available).
Example: AWS Installations
mount -t wekafs -o num_cores=2 backend1,backend2,backend3/my_fs /mnt/weka
Running this command on an AWS EC2 instance allocates two cores (multiple-frontends), attaches and configures two ENIs on the new client. The client attempts to rejoin the cluster through all three backends specified in the command line.
For stateless clients, the first mount
command installs the weka client software and joins the cluster). Any subsequent mount
command, can either use the same syntax or just the persistent/per-mount parameters as defined in Mounting Filesystems since it is not necessary to join a cluster.
It is now possible to access Weka filesystems via the mount-point, e.g., by cd /mnt/weka/
command.
After the execution of anumount
command, which unmounts the last Weka filesystem, the client is disconnected from the cluster and will be uninstalled by the agent. Consequently, executing a new mount
command requires the specification of the cluster, cores, and networking parameters again.
When running in AWS, the instance IAM role must provide permissions to several AWS APIs (see the IAM role created in template section).
Memory allocation for a client is predefined. To change the memory allocation, contact the Customer Success Team.
Remount of stateless clients options
Mount options marked as Remount Supported
in the above table can be remounted (using mount -o remount
). When a mount option is not set in the remount operation, it will retain its current value. To set a mount option back to its default value, use the default
modifier (e.g., memory_mb=default)
.
Set mount option default values
The defaults of the mount options qos_max_throughput_mbps
and qos_preferred_throughput_mbps
have no limit.
The cluster admin can set these default values to meet the organization's requirements, reset them to the initial default values (no limit), or show the existing values.
The mount option defaults are only relevant for new mounts performed and do not influence the existing ones.
Commands:
weka cluster mount-defaults set
weka cluster mount-defaults reset
weka cluster mount-defaults show
To set the mount option default values, run the following command:
Parameters
Option | Description |
---|---|
| Sets the default value for the |
| Sets the default value for the |
Advanced network configuration by mount options
When using a stateless client, it is possible to alter and control many different networking options, such as:
Virtual functions
IPs
Gateway (in case the client is on a different subnet)
Physical network devices (for performance and high availability)
UDP mode
Use -o net=<netdev>
mount option with the various modifiers as described below.
<netdev>
is either the name, MAC address, or PCI address of the physical network device (can be a bond device) to allocate for the client.
When using wekafs
mounts, both clients and backends should use the same type of networking technology (either IB or Ethernet).
IP, subnet, gateway, and virtual functions
For higher performance, the usage of multiple Frontends may be required. When using a NIC other than Mellanox or Intel E810 or mounting a DPDK client on a VM, it is required to use SR-IOV to expose a VF of the physical device to the client. Once exposed, it can be configured via the mount command.
To assign the VF IP addresses or when the client resides in a different subnet and routing is needed in the data network, usenet=<netdev>/[ip]/[bits]/[gateway]
.
ip, bits, gateway
are optional. If these options are not provided, the WEKA system performs one of the following depending on the environment:
Cloud environment: The WEKA system deduces the values of the
ip, bits, gateway
options.On-premises environment: The WEKA system allocates values to the
ip, bits, gateway
options based on the cluster default network. Failure to set the default network may result in the WEKA cluster failing to allocate an IP address for the client.Ensure that the WEKA cluster default data networking is configured prior to running the mount command. For details, see Configure default data networking (optional).
Example: allocate two cores and a single physical network device (intel0)
The following command configures two VFs for the device and assign each one of them to one of the frontend processes. The first container receives a 192.168.1.100 IP address, and the second uses a 192.168.1.101 IP address. Both IPs have 24 network mask bits and a default gateway of 192.168.1.254.
Multiple physical network devices for performance and high availability
For performance or high availability, it is possible to use more than one physical network device.
Using multiple physical network devices for better performance
It's easy to saturate the bandwidth of a single network interface when using WekaFS. For higher throughput, it is possible to leverage multiple network interface cards (NICs). The -o net
notation shown in the examples above can be used to pass the names of specific NICs to the WekaFS server driver.
For example, the following command will allocate two cores and two physical network devices for increased throughput:
Using multiple physical network devices for high availability configuration
Multiple NICs can also be configured to achieve redundancy and higher throughput for a complete, highly available solution. For that, use more than one physical device as previously described, and also, specify the client management IPs using -o mgmt_ip=<ip>+<ip2>
command-line option.
For example, the following command uses two network devices for high availability and allocate both devices to four Frontend processes on the client. The modifier ha
is used here, which stands for using the device on all processes.
Advanced mounting options for multiple physical network devices
With multiple Frontend processes (as expressed by -o num_cores
), it is possible to control what processes use what NICs. This can be accomplished through the use of special command line modifiers called slots. In WekaFS, slot is synonymous with a process number. Typically, the first WekaFS Frontend process will occupy slot 1, then the second - slot 2 and so on.
Examples of slot notation include s1
, s2
, s2+1
, s1-2
, slots1+3
, slot1
, slots1-4
, where -
specifies a range of devices, while +
specifies a list. For example, s1-4
implies slots 1, 2, 3, and 4, while s1+4
specifies slots 1 and 4.
For example, in the following command, mlnx0
is bound to the second Frontend process whilemlnx1
to the first one for improved performance.
For example, in the following mounting command, two cores (two Frontend processes) and two physical network devices (mlnx0
, mlnx1
) are allocated. By explicitly specifying s2+1
, s1-2
modifiers for network devices, both devices will be used by both Frontend processes. Notation s2+1
stands for the first and second processes, while s1-2
stands for the range of 1 to 2, and are effectively the same.
Related topic
High Availability (in the WEKA Networking topic)
UDP mode
If DPDK cannot be used, you can use the WEKA filesystem UDP networking mode through the kernel. Use net=udp
in the mount command to set the UDP networking mode, for example:
A client in UDP mode cannot be configured in high availability mode (ha
). However, the client can still work with a highly available cluster.
Providing multiple IPs in the <mgmt-ip> in UDP mode uses their network interfaces for more bandwidth, which can be useful in RDMA environments rather than using only one NIC.
Related topic
UDP mode (in the WEKA Networking topic)
Mount a filesystem using fstab
Using the fstab (filesystem table) enables automatic remount after reboot. It applies to stateless clients running on an OS that supports systemd
, such as RHEL/CentOS 8.0 and up, Ubuntu 18.04 and up, and Amazon Linux 2 LTS.
Before you begin
If the mount point you want to set in the fstab is already mounted, unmount it before setting the fstab file.
Procedure
Remove the
/etc/init.d/weka-agent
file.Create a file named
weka-agent.service
with the following content and save it in/etc/systemd/system
.
Run the following command:
Create a mount point. Example:
mkdir -p /mnt/weka/my_fs
Edit
/etc/fstab
file.
fstab structure
fstab example
fstab structure descriptions
Backend servers/my_fs: A comma-separated list of backend servers with the filesystem name
Mount point: If the client mounts multiple clusters, specify a unique name for each client container. Example: For two client containers, set
container_name=client1
andcontainer_name=client2
.Filesystem type:
wekafs
Mount options:
Systemd mount options:
x-systemd.after=weka-agent.service,x-systemd.mount-timeout=infinity,_netdev
You can set themount-timeout
based on your preferences, such as180
seconds. This flexibility allows you to customize the timeout according to your specific system needs.
Mount the the filesystem to test the fstab setting by running the command, for example:
mount /mnt/weka/my_fs
To test the fstab implementation, reboot the server. WEKA creates the mounts for the next boot.
The filesystem is mounted automatically after server reboot.
Mount a filesystem using autofs
Procedure:
Install
autofs
on the server using one of the following commands according to your deployment:
On Red Hat or CentOS:
On Debian or Ubuntu:
2. To create the autofs
configuration files for Weka filesystems, do one of the following
depending on the client type:
For a stateless client, run the following commands (specify the backend names as parameters):
For a persistent client, run the following commands:
3. Restart the autofs
service:
4. The configuration is distribution-dependent. Verify that the service is configured to start
automatically after restarting the server. Run the following command:
systemctl is-enabled autofs.
If the output is enabled
the service is configured to start automatically.
Example: In Amazon Linux, you can verify that the autofs
service is configured to start automatically by running the command chkconfig
.
If the output is on
for the current runlevel (you can check with therunlevel
command), autofs
is enabled upon restart.
Once you complete this procedure, it is possible to access Weka filesystems using the command cd /mnt/weka/<fs-name>
.
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