When default parameters are set in a request message, we get the client
connection using the session's origin. But it is not necessarily a
conncection. For instance, for health checks, thanks to recent changes, it may
be a check object. At this step, the client connection may be NULL. Thus, we
must be sure to have a client connection before using it.
This patch must be backported to 2.1.
It is now possible to force the mux protocol for a tcp-check based health check
using the server keyword "check-proto". If set, this parameter overwrites the
server one.
In the same way, a "proto" parameter has been added for tcp-check and http-check
connect rules. If set, this mux protocol overwrites all others for the current
connection.
First, when a server health check is initialized, it inherits the mux protocol
from the server if it is not already specified. Because there is no option to
specify the mux protocol for the checks, it is always inherited from the server
for now.
Then, if the connect rule is configured to use the server options, the mux
protocol of the check is used, if defined. Of course, if a mux protocol is
already defined for the connect rule, it is used in priority. But for now, it is
not possible.
Thus, if a server is configured to use, for instance, the h2 protocol, it is
possible to do the same for the health-checks.
No backport needed.
The documentation about the comment argument for some tcp-check and http-check
directives was missing. As well as the description of "tcp-check comment" and
"http-check comment" directives.
This reverts commit 1979943c30ef285ed04f07ecf829514de971d9b2.
Captures in comment was only used when a tcp-check expect based on a negative
regex matching failed to eventually report what was captured while it was not
expected. It is a bit far-fetched to be useable IMHO. on-error and on-success
log-format strings are far more usable. For now there is few check sample
fetches (in fact only one...). But it could be really powerful to report info in
logs.
HTTP health-checks now use HTX multiplexers. So it is important to really send
the amount of outgoing data for such checks because the HTX buffers appears
always full.
No backport needed.
Since all tcp-check rulesets are globally stored, it is a problem to use
list. For configuration with many backends, the lookups in list may be costly
and slow downs HAProxy startup. To solve this problem, tcp-check rulesets are
now stored in a tree.
When some data are scheduled to be sent, we must be sure to subscribe for sends
if nothing was sent. Because of a bug, when nothing was sent, connection errors
are checks. If no error is found, we exit, waiting for more data, without any
subcription on send events.
No need to backport.
Instead of accessing directly to the ist fields, the ist API is used instead. To
get its length or its pointer, to release it or to duplicate it. It is more
readable this way.
The patch is not obvious at the first glance. But it is just a reorg. Functions
have been grouped and ordered in a more logical way. Some structures and flags
are now private to the checks module (so moved from the .h to the .c file).
Thanks to previous change, it is now possible to removed all code handling pure
tcp checks. Now every connection based health-checks are handled by the
tcpcheck_main() function. __event_srv_chk_w() and __event_srv_chk_r() have been
removed. And all connection establishment is handled at one place.
Defaut health-checks, without any option, doing only a connection check, are now
based on tcp-checks. An implicit default tcp-check connect rule is used. A
shared tcp-check ruleset, name "*tcp-check" is created to support these checks.
When a tcp-check connect rule is evaluated, the mux protocol corresponding to
the health-check is chosen. So for TCP based health-checks, the mux-pt is
used. For HTTP based health-checks, the mux-h1 is used. The connection is marked
as private to be sure to not ruse regular HTTP connection for
health-checks. Connections reuse will be evaluated later.
The functions evaluating HTTP send rules and expect rules have been updated to
be HTX compliant. The main change for users is that HTTP health-checks are now
stricter on the HTTP message format. While before, the HTTP formatting and
parsing were minimalist, now messages should be well formatted.
This function is unused for now. But it will have be used to install a mux for
an outgoing connection openned in a health-check context. In this case, the
session's origin is the check itself, and it is used to know the mode, HTTP or
TCP, depending on the tcp-check type and not the proxy mode. The check is also
used to get the mux protocol if configured.
It is not set and not used for now, but it will be possible to force the mux
protocol thanks to this patch. A mux proto field is added to the checks and to
tcp-check connect rules.
Before, the server was used as origin during session creation. It was only used
to get the check associated to the server when a variable is get or set in the
check scope or when a check sample fetch was called. So it seems easier to use
the check as origin of a session. It is also more logical becaues the session is
created by the health-check itself and not its server.
A dedicated function is now used to received data. fundamentally, it should do
the same operations than before. But the way data are received has been reworked
to be closer to the si_cs_recv() function.
First tests before executing the loop on tcp-check rules in tcpcheck_main()
function have been slightly modified to be more explicit and easier to
understand.
HTTP health-checks are now internally based on tcp-checks. Of course all the
configuration parsing of the "http-check" keyword and the httpchk option has
been rewritten. But the main changes is that now, as for tcp-check ruleset, it
is possible to perform several send/expect sequences into the same
health-checks. Thus the connect rule is now also available from HTTP checks, jst
like set-var, unset-var and comment rules.
Because the request defined by the "option httpchk" line is used for the first
request only, it is now possible to set the method, the uri and the version on a
"http-check send" line.
the get_last_tcpcheck_rule() function iters on a rule list in the reverse order
and returns the first non comment and non action-kw rule. If no such rule is
found, NULL is returned.
Instead of having 2 independent integers, used as boolean values, to know if the
expect rule is invered and to know if the matching regexp has captures, we know
use a 32-bits bitfield.
All tcp-check rules are now stored in the globla shared list. The ones created
to parse a specific protocol, for instance redis, are already stored in this
list. Now pure tcp-check rules are also stored in it. The ruleset name is
created using the proxy name and its config file and line. tcp-check rules
declared in a defaults section are also stored this way using "defaults" as
proxy name.
For now, all tcp-check ruleset are stored in a list. But it could be a bit slow
to looks for a specific ruleset with a huge number of backends. So, it could be
a good idea to use a tree instead.
It is now possible to specified the healthcheck status to use on success of a
tcp-check rule, if it is the last evaluated rule. The option "ok-status"
supports "L4OK", "L6OK", "L7OK" and "L7OKC" status.
A shared tcp-check ruleset is now created to support agent checks. The following
sequence is used :
tcp-check send "%[var(check.agent_string)] log-format
tcp-check expect custom
The custom function to evaluate the expect rule does the same that it was done
to handle agent response when a custom check was used.
Parsing of following keywords have been moved in checks.c file : addr, check,
check-send-proxy, check-via-socks4, no-check, no-check-send-proxy, rise, fall,
inter, fastinter, downinter and port.
A share tcp-check ruleset is now created to support SPOP checks. This way no
extra memory is used if several backends use a SPOP check.
The following sequence is used :
tcp-check send-binary SPOP_REQ
tcp-check expect custom min-recv 4
The spop request is the result of the function
spoe_prepare_healthcheck_request() and the expect rule relies on a custom
function calling spoe_handle_healthcheck_response().
A shared tcp-check ruleset is now created to support LDAP check. This way no
extra memory is used if several backends use a LDAP check.
The following sequance is used :
tcp-check send-binary "300C020101600702010304008000"
tcp-check expect rbinary "^30" min-recv 14 \
on-error "Not LDAPv3 protocol"
tcp-check expect custom
The last expect rule relies on a custom function to check the LDAP server reply.
A share tcp-check ruleset is now created to support MySQL checks. This way no
extra memory is used if several backends use a MySQL check.
One for the following sequence is used :
## If no extra params are set
tcp-check connect default linger
tcp-check expect custom ## will test the initial handshake
## If the username is defined
tcp-check connect default linger
tcp-check send-binary MYSQL_REQ log-format
tcp-check expect custom ## will test the initial handshake
tcp-check expect custom ## will test the reply to the client message
The log-format hexa string MYSQL_REQ depends on 2 preset variables, the packet
header containing the packet length and the sequence ID (check.header) and the
username (check.username). If is also different if the "post-41" option is set
or not. Expect rules relies on custom functions to check MySQL server packets.
A shared tcp-check ruleset is now created to support postgres check. This way no
extra memory is used if several backends use a pgsql check.
The following sequence is used :
tcp-check connect default linger
tcp-check send-binary PGSQL_REQ log-format
tcp-check expect !rstring "^E" min-recv 5 \
error-status "L7RSP" on-error "%[check.payload(6,0)]"
tcp-check expect rbinary "^520000000800000000 min-recv "9" \
error-status "L7STS" \
on-success "PostgreSQL server is ok" \
on-error "PostgreSQL unknown error"
The log-format hexa string PGSQL_REQ depends on 2 preset variables, the packet
length (check.plen) and the username (check.username).
A share tcp-check ruleset is now created to support smtp checks. This way no
extra memory is used if several backends use a smtp check.
The following sequence is used :
tcp-check connect default linger
tcp-check expect rstring "^[0-9]{3}[ \r]" min-recv 4 \
error-status "L7RSP" on-error "%[check.payload(),cut_crlf]"
tcp-check expect rstring "^2[0-9]{2}[ \r]" min-recv 4 \
error-status "L7STS" \
on-error %[check.payload(4,0),ltrim(' '),cut_crlf] \
status-code "check.payload(0,3)"
tcp-echeck send "%[var(check.smtp_cmd)]\r\n" log-format
tcp-check expect rstring "^2[0-9]{2}[- \r]" min-recv 4 \
error-status "L7STS" \
on-error %[check.payload(4,0),ltrim(' '),cut_crlf] \
on-success "%[check.payload(4,0),ltrim(' '),cut_crlf]" \
status-code "check.payload(0,3)"
The variable check.smtp_cmd is by default the string "HELO localhost" by may be
customized setting <helo> and <domain> parameters on the option smtpchk
line. Note there is a difference with the old smtp check. The server gretting
message is checked before send the HELO/EHLO comand.
A shared tcp-check ruleset is now created to support ssl-hello check. This way
no extra memory is used if several backends use a ssl-hello check.
The following sequence is used :
tcp-check send-binary SSLV3_CLIENT_HELLO log-format
tcp-check expect rbinary "^1[56]" min-recv 5 \
error-status "L6RSP" tout-status "L6TOUT"
SSLV3_CLIENT_HELLO is a log-format hexa string representing a SSLv3 CLIENT HELLO
packet. It is the same than the one used by the old ssl-hello except the sample
expression "%[date(),htonl,hex]" is used to set the date field.
A share tcp-check ruleset is now created to support redis checks. This way no
extra memory is used if several backends use a redis check.
The following sequence is used :
tcp-check send "*1\r\n$4\r\nPING\r\n"
tcp-check expect string "+PONG\r\n" error-status "L7STS" \
on-error "%[check.payload(),cut_crlf]" on-success "Redis server is ok"
