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
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.
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 establish the connection opened by a
tcp-check connect rule using upstream socks4 proxy. Info from the socks4
parameter on the server are used.
Register the custom action rules "set-var" and "unset-var", that will
call the parse_store() command upon parsing.
These rules are thus built and integrated to the tcp-check ruleset, but
have no further effect for the moment.
Add a dedicated vars scope for checks. This scope is considered as part of the
session scope for accounting purposes.
The scope can be addressed by a valid session, even embryonic. The stream is not
necessary.
The scope is initialized after the check session is created. All variables are
then pruned before the session is destroyed.
Create a session for each healthcheck relying on a tcp-check ruleset. When such
check is started, a session is allocated, which will be freed when the check
finishes. A dummy static frontend is used to create these sessions. This will be
useful to support variables and sample expression. This will also be used,
later, by HTTP healthchecks to rely on HTTP muxes.
The loop in tcpcheck_main() function is quite hard to understand. Depending
where we are in the loop, The current_step is the currentely executed rule or
the one to execute on the next call to tcpcheck_main(). When the check result is
reported, we rely on the rule pointed by last_started_step or the one pointed by
current_step. In addition, the loop does not use the common list_for_each_entry
macro and it is thus quite confusing.
So the loop has been totally rewritten and splitted to several functions to
simplify its reading and its understanding. Tcp-check rules are evaluated in
dedicated functions. And a common for_each loop is used and only one rule is
referenced, the current one.
After the configuration parsing, when its validity check, an implicit tcp-check
connect rule is added in front of the tcp-check ruleset if the first non-comment
rule is not a connect one. This implicit rule is flagged to use the default
check parameter.
This means now, all tcp-check rulesets begin with a connect and are never
empty. When tcp-check healthchecks are used, all connections are thus handled by
tcpcheck_main() function.
To allow reusing these blocks without consuming more memory, their list
should be static and share-able accross uses. The head of the list will
be shared as well.
It is thus necessary to extract the head of the rule list from the proxy
itself. Transform it into a pointer instead, that can be easily set to
an external dynamically allocated head.
Parse back-references in comments of tcp-check expect rules. If references are
made, capture groups in the match and replace references to it within the
comment when logging the error. Both text and binary regex can caputre groups
and reference them in the expect rule comment.
[Cf: I slightly updated the patch. exp_replace() function is used instead of a
custom one. And if the trash buffer is too small to contain the comment during
the substitution, the comment is ignored.]
The rbinary match works similarly to the rstring match type, however the
received data is rewritten as hex-string before the match operation is
done.
This allows using regexes on binary content even with the POSIX regex
engine.
[Cf: I slightly updated the patch. mem2hex function was removed and dump_binary
is used instead.]
Allow declaring tcpcheck connect commands with a new parameter,
"linger". This option will configure the connection to avoid using an
RST segment to close, instead following the four-way termination
handshake. Some servers would otherwise log each healthcheck as
an error.
Some expect rules cannot be satisfied due to inherent ambiguity towards
the received data: in the absence of match, the current behavior is to
be forced to wait either the end of the connection or a buffer full,
whichever comes first. Only then does the matching diagnostic is
considered conclusive. For instance :
tcp-check connect
tcp-check expect !rstring "^error"
tcp-check expect string "valid"
This check will only succeed if the connection is closed by the server before
the check timeout. Otherwise the first expect rule will wait for more data until
"^error" regex matches or the check expires.
Allow the user to explicitly define an amount of data that will be
considered enough to determine the value of the check.
This allows succeeding on negative rstring rules, as previously
in valid condition no match happened, and the matching was repeated
until the end of the connection. This could timeout the check
while no error was happening.
[Cf: I slighly updated the patch. The parameter was renamed and the value is a
signed integer to support -1 as default value to ignore the parameter.]
When receiving additional data while chaining multiple tcp-check expects,
previous inverse expects might have a different result with the new data. They
need to be evaluated again against the new data.
Add a pointer to the first inverse expect rule of the current expect chain
(possibly of length one) to each expect rule. When receiving new data, the
currently evaluated tcp-check rule is set back to this pointed rule.
Fonctionnaly speaking, it is a bug and it exists since the introduction of the
feature. But there is no way for now to hit it because when an expect rule does
not match, we wait for more data, independently on the inverse flag. The only
way to move to the following rule is to be sure no more data will be received.
This patch depends on the commit "MINOR: mini-clist: Add functions to iterate
backward on a list".
[Cf: I slightly updated the patch. First, it only concerns inverse expect
rule. Normal expect rules are not concerned. Then, I removed the BUG tag
because, for now, it is not possible to move to the following rule when the
current one does not match while more data can be received.]
Replace the generic integer with an enumerated list. This allows light
type check and helps debugging (seeing action = 2 in the struct is not
helpful).
This options is used to force a non-SSL connection to check a SSL server or to
invert a check-ssl option inherited from the default section. The use_ssl field
in the check structure is used to know if a SSL connection must be used
(use_ssl=1) or not (use_ssl=0). The server configuration is used by default.
The problem is that we cannot distinguish the default case (no specific SSL
check option) and the case of an explicit non-SSL check. In both, use_ssl is set
to 0. So the server configuration is always used. For a SSL server, when
no-check-ssl option is set, the check is still performed using a SSL
configuration.
To fix the bug, instead of a boolean value (0=TCP, 1=SSL), we use a ternary value :
* 0 = use server config
* 1 = force SSL
* -1 = force non-SSL
The same is done for the server parameter. It is not really necessary for
now. But it is a good way to know is the server no-ssl option is set.
In addition, the PR_O_TCPCHK_SSL proxy option is no longer used to set use_ssl
to 1 for a check. Instead the flag is directly tested to prepare or destroy the
server SSL context.
This patch should be backported as far as 1.8.
The 'http-check send' directive have been added to add headers and optionnaly a
payload to the request sent during HTTP healthchecks. The request line may be
customized by the "option httpchk" directive but there was not official way to
add extra headers. An old trick consisted to hide these headers at the end of
the version string, on the "option httpchk" line. And it was impossible to add
an extra payload with an "http-check expect" directive because of the
"Connection: close" header appended to the request (See issue #16 for details).
So to make things official and fully support payload additions, the "http-check
send" directive have been added :
option httpchk POST /status HTTP/1.1
http-check send hdr Content-Type "application/json;charset=UTF-8" \
hdr X-test-1 value1 hdr X-test-2 value2 \
body "{id: 1, field: \"value\"}"
When a payload is defined, the Content-Length header is automatically added. So
chunk-encoded requests are not supported yet. For now, there is no special
validity checks on the extra headers.
This patch is inspired by Kiran Gavali's work. It should fix the issue #16 and
as far as possible, it may be backported, at least as far as 1.8.
Server address and port may change at runtime. So the address and port passed as
arguments and as environment variables when an external check is executed must
be updated. The current number of connections on the server was already updated
before executing the command. So the same mechanism is used for the server
address and port. But in addition, command arguments are also updated.
This patch must be backported to all stable versions. It should fix the
issue #577.
If haproxy fails to start and emits an alert, then it can be useful
to have it also emit the version and the path used to load it. Some
users may be mistakenly launching the wrong binary due to a misconfigured
PATH variable and this will save them some troubleshooting time when it
reports that some keywords are not understood.
What we do here is that we *try* to extract the binary name from the
AUX vector on glibc, and we report this as a NOTICE tag before the
very first alert is emitted.
Since some systems switched to service managers which hide all warnings
by default, some users are not aware of some possibly important warnings
and get caught too late with errors that could have been detected earlier.
This patch adds a new global keyword, "zero-warning" and an equivalent
command-line option "-dW" to refuse to start in case any warning is
detected. It is recommended to use these with configurations that are
managed by humans in order to catch mistakes very early.
This helps quickly checking if the config produces any warning. For
this we reuse the "warned" bit field to add a new WARN_ANY bit that is
set by ha_warning(). The rest of the bit field was also cleaned from
unused bits.
In 'commit ssl cert', instead of trying to regenerate a list of filters
from the SNIs, use the list provided by the crtlist_entry used to
generate the ckch_inst.
This list of filters doesn't need to be free'd anymore since they are
always reused from the crtlist_entry.
The dump and show ssl crt-list commands does the same thing, they dump
the content of a crt-list, but the 'show' displays an ID in the first
column. Delete the 'dump' command so it is replaced by the 'show' one.
The old 'show' command is replaced by an '-n' option to dump the ID.
And the ID which was a pointer is replaced by a line number and placed
after colons in the filename.
Example:
$ echo "show ssl crt-list -n kikyo.crt-list" | socat /tmp/sock1 -
# kikyo.crt-list
kikyo.pem.rsa:1 secure.domain.tld
kikyo.pem.ecdsa:2 secure.domain.tld
When updating a ckch_store we may want to update its pointer in the
crtlist_entry which use it. To do this, we need the list of the entries
using the store.
The instances were wrongly inserted in the crtlist entries, all
instances of a crt-list were inserted in the last crt-list entry.
Which was kind of handy to free all instances upon error.
Now that it's done correctly, the error path was changed, it must
iterate on the entries and find the ckch_insts which were generated for
this bind_conf. To avoid wasting time, it stops the iteration once it
found the first unsuccessful generation.
In order to be able to add new certificate in a crt-list, we need the
list of bind_conf that uses this crt-list so we can create a ckch_inst
for each of them.
Add a counter to know the current number of used connections, as well as the
max, this will be used later to refine the algorithm used to kill idle
connections, based on current usage.
With server-template was introduced the possibility to scale the
number of servers in a backend without needing a configuration change
and associated reload. On the other hand it became impractical to
write use-server rules for these servers as they would only accept
existing server labels as argument. This patch allows the use of
log-format notation to describe targets of a use-server rules, such
as in the example below:
listen test
bind *:1234
use-server %[hdr(srv)] if { hdr(srv) -m found }
use-server s1 if { path / }
server s1 127.0.0.1:18080
server s2 127.0.0.1:18081
If a use-server rule is applied because it was conditionned by an
ACL returning true, but the target of the use-server rule cannot be
resolved, no other use-server rule is evaluated and we fall back to
load balancing.
This feature was requested on the ML, and bumped with issue #563.
In connect_server(), if we no longer have any idle connections for the
current thread, attempt to use the new "takeover" mux method to steal a
connection from another thread.
This should have no impact right now, given no mux implements it.
Make the "list" element a struct mt_list, and explicitely use
list_from_mt_list to get a struct list * where it is used as such, so that
mt_list_for_each_entry will be usable with it.
Add a new mux method, "takeover", that will attempt to make the current thread
responsible for the connection.
It should return 0 on success, and non-zero on failure.
Revamp the server connection lists. We know have 3 lists :
- idle_conns, which contains idling connections
- safe_conns, which contains idling connections that are safe to use even
for the first request
- available_conns, which contains connections that are not idling, but can
still accept new streams (those are HTTP/2 or fastcgi, and are always
considered safe).
Move the definition of WDTSIG and DEBUGSIG from wdt.c and debug.c into
types/signal.h, so that we can access them in another file.
We need those definition to avoid blocking those signals when running
__signal_process_queue().
This should be backported to 2.1, 2.0 and 1.9.
