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io-pkt-v4, io-pkt-v4-hc, io-pkt-v6-hc
Networking manager
Syntax:
io-pkt-variant [-d driver [driver_options]] [-i instance] [-p protocol [protocol_options]] [-t threads] [-v]
where variant is one of v4, v4-hc, or v6-hc.
Runs on:
Neutrino
Options:
- -d driver [driver_options]
- Start the specified
devn-*
or
devnp-*
driver:
- You can specify driver without the devn- or devnp- prefix or the .so extension. For example, to start the devnp-i82544.so driver, specify -d i82544. If you specify the driver this way, io-pkt* looks for a devnp- version first. If there isn't one, io-pkt* loads the legacy io-net (devn-) version, using a special “shim” layer, devnp-shim.so.
- If you want to load a specific version of a driver, specify the full path of the module (e.g. /lib/dll/devn-i82544.so).
The driver_options argument is a list of driver-specific options that the stack passes to the driver.

Use commas, not spaces, to separate the options. The stack processes various driver options; for more information, see “Generic driver options,” below.
- -i instance
- The stack instance number, which is useful if you're running multiple
instances of io-pkt.
The io-pkt manager will service mount requests of type
io-pktX, where X is the instance number.
For example:
io-pkt-v4 -i1 -ptcpip prefix=/alt mount -Tio-pkt1 /lib/dll/devnp-i82544.so
- -p protocol [protocol_options]
- The protocol to start, followed by a list of protocol-specific options.

Use commas, not spaces, to separate the options. The available protocols include:
Protocol Module autoip lsm-autoip.so qnet lsm-qnet.so tcpip The stack includes TCP/IP; you need to specify this protocol only if you want to pass additional parameters (e.g. prefix=) to it. For more information about the options, see below. - -S
- Don't register a SIGSEGV handler to quiesce the hardware if a segmentation violation occurs. This can help with debugging if it isn't possible to get a backtrace to the original code that generated the SIGSEGV through the signal handler.
- -t threads
- The number of processing threads to create. By default, one thread is created per CPU. These threads are the packet-processing threads that operate at Layer2 and may become the stack thread. For more information, see the Overview chapter of the QNX Neutrino Core Networking User's Guide.
- -v
- If any errors occur while loading drivers and protocols, io-pkt sends messages to slogger. If you specify this option, io-pkt also displays them on the console.
If you specify the -p tcpip protocol, the protocol_options list can consist of one or more of the following, separated by commas without whitespace:
- bigpage_strict
- If the value of the pagesize option is bigger than sysconf(_SC_PAGESIZE), it's used only for the mbuf and cluster pools unless you also specify this option, in which case the page size is used for all pools.
- cache=0
- Disable the caching of packet buffers. This should be needed only as a debugging facility.
- confstr_monitor
- Monitor changes to configuration strings, in particular CS_HOSTNAME. By default, io-pkt gets the hostname once at startup.
- enmap
- Prevent automatic stack mapping of enXX interface names to the actual interface names. By default, the stack automatically maps the first registered interface to en0 (if a real en0 isn't present), the second interface to en1, and so on, in order to preserve backwards compatibility with io-net-style command lines.
- fastforward=X
- Enable (1) or disable (0) fastforwarding path. This is useful for gateways. This option enables, and is enabled by, forward; to enable only forward, specify forward,fastforward=0.
- forward
- Enable forwarding of IPv4 packets between interfaces; this enables fastforward by default. The default is off.
- forward6
- (io-pkt-v6-hc only) Enable forwarding of IPv6 packets between interfaces; off by default.
- ipsec
- (io-pkt-v4-hc and io-pkt-v6-hc only) Enable IPsec support; off by default.
- mbuf_cache=X
- As mbufs are freed after use, rather than returning them to the internal pool for general consumption, up to X mbufs are cached per thread to allow quicker retrieval on the next allocation.
- mclbytes=size
- The mbuf cluster size.
A cluster is the largest amount of contiguous memory used by
an mbuf.
If the MTU is larger than a cluster, multiple clusters are used to hold
the packet.
The default cluster size is 2 KB (to fit a standard 1500-byte Ethernet
packet).
Specifying the cluster size can improve performance; for more information, see “Jumbo packets and hardware checksumming” in the Network Drivers chapter of the QNX Neutrino Core Networking User's Guide.
- pagesize=X
- The smallest amount of data allocated each time for the internal memory pools. This quantum is then carved into chunks of varying size, depending on the pool.
- pkt_cache=X
- As mbuf and cluster combinations are freed after use, rather than return them to the internal pool for general consumption, up to X mbufs and clusters are cached per thread to allow quicker retrieval on the next allocation.
- prefix=/path
- The path to prepend to the traditional /dev/socket.
The is useful when running multiple stacks.
Clients can target a particular stack by using the SOCK
environmental variable.
For example:
# io-pkt -ptcpip prefix=/alt # SOCK=/alt ifconfig -a
- random
- Use /dev/random as the source of random data. By default, io-pkt uses a builtin pseudo-random number generator.
- recv_ctxt=X
- Specify the size of the receive context buffer, in bytes. The default is 65536; the minimum is 2048.
- reuseport_unicast
- If using the SO_REUSEPORT socket option, received unicast UDP packets are delivered to all sockets bound to the port. The default is to deliver only multicast and broadcast to all sockets.
- rx_prio=X
rx_pulse_prio=X - The priority for receive threads to use (the default is 21). A driver-specific priority option (if supported by the driver) can override this priority.
- somaxconn=X
- Specify the value of SOMAXCONN, the maximum length of the listen queue used to accept new TCP connections. The minimum is the value in <sys/socket.h>.
- stacksize=X
- Specify the size of each thread's stack, in bytes. The default is 4096.
- threads_incr=X
- If the supply of threads is exhausted, increment their number by this amount, up to the value of threads_max. The default is 25.
- threads_max=X
- Specify the maximum number of threads. The default is 200.
- threads_min=X
- Specify the minimum number of threads. The default is 15, and the minimum is 4.
Description:
The io-pkt manager provides support for Internet domain sockets, Unix domain sockets, and dynamically loaded networking modules. It comes in several stack variants:
- io-pkt-v4
- An IPv4 memory-reduced variant which doesn't support:
- IPv6
- Crypto / IPSec
- 802.11 a/b/g WiFi
- Bridging
- GRE / GRF
- Multicast routing
- Multipoint PPP
- io-pkt-v4-hc
- IPv4 version of the stack that has full encryption and Wi-Fi capability built in and includes hardware accelerated cryptography capability (Fast IPsec).
- io-pkt-v6-hc
- IPv6 version of the stack (includes IPv4 as part of v6) that has full encryption and Wi-Fi capability, also with hardware accelerated cryptography.
You can use the mount command to start drivers after you've launched io-pkt*. If you want to pass options to the driver, use the -o option before the name of the shared object. For example:
mount -T io-pkt -o mac=12345678 devnp-bge.so
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Generic driver options
The stack processes a generic name= option that lets you override the default interface prefix used for network drivers. For example:
io-pkt-v4 -di82544 name=en
starts the devnp-i82544.so driver with the io-net-style interface naming convention (enXX). You can also use this option to assign interface names based on (for example) functionality:
io-pkt-v4 -di82544 pci=0,name=wan
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This option doesn't work with legacy io-net legacy drivers. If you attempt to use this option with a devn- driver, the driver won't be loaded, and the log will include an “unknown option” error. |
The stack also processes the following driver options for all USB drivers using the NetBSD-to-QNX conversion library to let you identify a particular USB device using information obtained from running usb -v:
- did=ID
- Device product ID.
- vid=ID
- Device vendor ID.
- devno=addr
- Device address, as reported by the usb utility.
- busno=num
- Host controller, as reported by the usb utility
For example:
io-pkt-v4-hc -drum did=0x0020,vid=0x13b1,devno=1,busno=1
Examples:
Start the v4 TCP/IP variant of io-pkt using the devnp-bcm1250.so driver on BCM91480A eth0:
io-pkt-v4 -d /lib/dll/devnp-bcm1250.so \ memrange=0x10064000,irq=0x80050024,mac=001122334455 ifconfig bcm0 10.184
See also:
devn-*, devnp-*, ifconfig, lsm-autoip.so, lsm-qnet.so, mount, umount
QNX Neutrino Core Networking User's Guide
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