Provided by: knot-dnsutils_3.3.4-1.1build2_amd64 
NAME
kxdpgun - XDP-powered DNS benchmarking tool
SYNOPSIS
kxdpgun [options] -i filename target_IP
DESCRIPTION
Powerful generator of DNS traffic, sending and receiving packets through XDP.
Queries are generated according to a textual file which is read sequentially in a loop until a configured
duration elapses. The order of queries is not guaranteed. Responses are received (unless disabled) and
counted, but not checked against queries.
The number of parallel threads is autodetected according to the number of queues configured for the
network interface.
Parameters
filename
Path to the queries file. See the description below regarding the file format.
target_IP
The IPv4 or IPv6 address of remote destination.
Options
-t, --duration seconds
Duration of traffic generation, specified as a decimal number in seconds (default is 5.0).
-T, --tcp[=debug_mode]
Send queries over TCP. See the list of optional debug modes below.
-U, --quic[=debug_mode]
Send queries over QUIC. See the list of optional debug modes below.
-Q, --qps queries
Number of queries-per-second (approximately) to be sent (default is 1000). The program is not
optimized for low speeds at which it may lose communication packets. The recommended minimum speed
is 2 packets per thread (Rx/Tx queue).
-b, --batch size
Send more queries in a batch. Improves QPS but may affect the counterpart's packet loss (default
is 10 for UDP and 1 for TCP/QUIC).
-r, --drop
Drop incoming responses. Improves QPS, but disables response statistics.
-p, --port number
Remote destination port (default is 53 for UDP/TCP, 853 for QUIC).
-F, --affinity cpu_spec
CPU affinity for all threads specified in the format [<cpu_start>][s<cpu_step>], where <cpu_start>
is the CPU ID for the first thread and <cpu_step> is the CPU ID increment for next thread (default
is 0s1).
-i, --infile filename
Path to a file with query templates.
-I, --interface interface
Network interface for outgoing communication. This can be useful in situations when the interfaces
are in a bond for example.
-l, --local localIP[/prefix]
Override the auto-detected source IP address. If an address range is specified instead, various
IPs from the range will be used for different queries uniformly (address range not supported in
the QUIC mode).
-L, --mac-local
Override auto-detected local MAC address.
-R, --mac-remote
Override auto-detected remote MAC address.
-v, --vlan id
Add VLAN 802.1Q header with the given id. VLAN offloading should be disabled.
-e, --edns-size size
EDNS UDP payload size, range 512-4096 (default is 1232). Note that over XDP the maximum supported
MTU is 1790.
-m, --mode mode
Set the XDP mode. Supported values are:
• auto (default) – the XDP mode is selected automatically to achieve the best performance, which
means that native driver support is preferred over the generic one, and zero-copy is used if
available.
• copy – the XDP socket copy mode is forced even if zero-copy is available. This can resolve
various driver issues, but at the cost of lower performance.
• generic – the generic XDP implementation is forced even if native implementation is available.
This mode doesn't require support from the driver nor hardware, but offers the worst
performance.
-G, --qlog path
Generate qlog files in the directory specified by path. The directory has to exist.
This option is ignored if not in the QUIC mode. The recommended usage is with --quic=R or with low
QPS. Otherwise, too many files are generated.
-h, --help
Print the program help.
-V, --version
Print the program version.
Queries file format
Each line describes a query in the form:
query_name query_type [flags]
Where query_name is a domain name to be queried, query_type is a record type name, and flags is a single
character:
E Send query with EDNS.
D Request DNSSEC (EDNS + DO flag).
TCP/QUIC debug modes
0 Perform full handshake for all connections (QUIC only).
1 Just send SYN (Initial) and receive SYN-ACK (Handshake).
2 Perform TCP/QUIC handshake and don't send anything, allow close initiated by counterpart.
3 Perform TCP/QUIC handshake and don't react further.
5 Send incomplete query (N-1 bytes) and don't react further.
7 Send query and don't ACK the response or anything further.
8 Don't close the connection and ignore close by counterpart.
9 Operate normally except for not ACKing the final FIN+ACK (TCP only).
R Instead of opening a connection for each query, reuse connections.
Signals
Sending USR1 signal to a running process triggers current statistics dump to the standard output.
NOTES
Linux kernel 4.18+ is required.
The utility has to be executed under root or with these capabilities: CAP_NET_RAW, CAP_NET_ADMIN,
CAP_SYS_ADMIN, CAP_IPC_LOCK, and CAP_SYS_RESOURCE (Linux < 5.11).
The utility allocates source UDP/TCP ports from the range 2000-65535.
EXIT VALUES
Exit status of 0 means successful operation. Any other exit status indicates an error.
EXAMPLES
Manually created queries file:
abc6.example.com. AAAA
nxdomain.example.com. A
notzone. A
a.example.com. NS E
ab.example.com. A D
abcd.example.com. DS D
Queries file generated from a zone file (Knot DNS format):
cat ZONE_FILE | awk "{print \$1,\$3}" | grep -E "(NS|DS|A|AAAA|PTR|MX|SOA)$" | sort -u -R > queries.txt
Basic usage:
# kxdpgun -i ~/queries.txt 2001:DB8::1
Using UDP with increased batch size:
# kxdpgun -t 20 -Q 1000000 -i ~/queries.txt -b 20 -p 8853 192.0.2.1
Using TCP:
# kxdpgun -t 20 -Q 100000 -i ~/queries.txt -T -p 8853 192.0.2.1
SEE ALSO
kdig(1).
AUTHOR
CZ.NIC Labs <https://www.knot-dns.cz>
COPYRIGHT
Copyright 2010–2024, CZ.NIC, z.s.p.o.