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"
It is now possible to set a custom function to evaluate a tcp-check expect
rule. It is an internal and not documentd option because the right pointer of
function must be set and it is not possible to express it in the
configuration. It will be used to convert some protocol healthchecks to
tcp-checks.
Custom functions must have the following signature:
enum tcpcheck_eval_ret (*custom)(struct check *, struct tcpcheck_rule *, int);
A list of variables is now associated to each tcp-check ruleset. It is more a
less a list of set-var expressions. This list may be filled during the
configuration parsing. The listed variables will then be set during each
execution of the tcp-check healthcheck, at the begining, before execution of the
the first tcp-check rule.
This patch is mandatory to convert all protocol checks to tcp-checks. It is a
way to customize shared tcp-check rulesets.
This option defines a sample expression, evaluated as an integer, to set the
status code (check->code) if a tcp-check healthcheck ends on the corresponding
expect rule.
These options define log-format strings used to produce the info message if a
tcp-check expect rule fails (on-error option) or succeeds (on-success
option). For this last option, it must be the ending rule, otherwise the
parameter is ignored.
It is now possible to extract information from the check input buffer using the
check.payload sample fetch. As req.payload or res.payload, an offset and a
length must be specified.
A new section has been added in the configuration manual. Now check sample
fetches will have to be documented under the section 7.3.7 (Fetching
health-check samples).
When a tcp-check healthcheck fails on a specific rule with no dedicated comment,
we look in previous rules if a comment rule is specified. Now, instead of doing
it during tcp-checks execution, we assign the comment to the corresponding rules
during the configuration parsing. So after HAProxy startup, no more comment
rules remains in a tcp-check ruleset.
It is now possible to specified the healthcheck status to use on error or on
timeout for tcp-check expect rules. First, to define the error status, the
option "error-status" must be used followed by "L4CON", "L6RSP", "L7RSP" or
"L7STS". Then, to define the timeout status, the option "tout-status" must be
used followed by "L4TOUT", "L6TOUT" or "L7TOUT".
These options will be used to convert specific protocol healthchecks (redis,
pgsql...) to tcp-check ones.
x
This converter tranform a integer to its binary representation in the network
byte order. Integer are already automatically converted to binary during sample
expression evaluation. But because samples own 8-bytes integers, the conversion
produces 8 bytes. the htonl converter do the same but for 4-bytes integer.
A global list to tcp-check ruleset can now be used to share common rulesets with
all backends without any duplication. It is mandatory to convert all specific
protocol checks (redis, pgsql...) to tcp-check healthchecks.
To do so, a flag is now attached to each tcp-check ruleset to know if it is a
shared ruleset or not. tcp-check rules defined in a backend are still directly
attached to the proxy and not shared. In addition a second flag is used to know
if the ruleset is inherited from the defaults section.
When a log-format string is parsed, if a sample fetch is found, the flag LW_REQ
is systematically added on the proxy. Unfortunately, this produce a warning
during HAProxy start-up when a log-format string is used for a tcp-check send
rule. Now this flag is only added if the parsed sample fetch depends on HTTP
information.
When a log-format string is evaluated, there is no reason to process sample
fetches only when a stream is defined. Several sample fetches are available
outside the stream scope. All others should handle calls without stream. This
patch is mandatory to support log-format string in tcp-check rules.
An extra parameter for tcp-check send rules can be specified to handle the
string or the hexa string as a log-format one. Using "log-format" option,
instead of considering the data to send as raw data, it is parsed as a
log-format string. Thus it is possible to call sample fetches to customize data
sent to a server. Of course, because we have no stream attached to healthchecks,
not all sample fetches are available. So be careful.
tcp-check set-var(check.port) int(8000)
tcp-check set-var(check.uri) str(/status)
tcp-check connect port var(check.port)
tcp-check send "GET %[check.uri] HTTP/1.0\r\n" log-format
tcp-check send "Host: %[srv_name]\r\n" log-format
tcp-check send "\r\n"
Since we have a session attached to tcp-check healthchecks, It is possible use
sample expression and variables. In addition, it is possible to add tcp-check
set-var rules to define custom variables. So, now, a sample expression can be
used to define the port to use to establish a connection for a tcp-check connect
rule. For instance:
tcp-check set-var(check.port) int(8888)
tcp-check connect port var(check.port)
With this option, it is now possible to use a specific address to open the
connection for a tcp-check connect rule. If the port option is also specified,
it is used in priority.
With this option, it is possible to open a connection from a tcp-check connect
rule using all parameter of the server line, like any other healthcheck. For
now, this parameter is exclusive with all other option for a tcp-check connect
rule.
With this option, it is possible to establish the connection opened by a
tcp-check connect rule using upstream socks4 proxy. Info from the socks4
parameter on the server are used.
