last_change was a member present in both proxy and server struct. It is
used as an age statistics to report the last update of the object.
Move last_change into fe_counters/be_counters. This is necessary to be
able to manipulate it through generic stat column and report it into
stats-file.
Note that there is a change for proxy structure with now 2 different
last_change values, on frontend and backend side. Special care was taken
to ensure that the value is initialized only on the proxy side. The
other value is set to 0 unless a listen proxy is instantiated. For the
moment, only backend counter is reported in stats. However, with now two
distinct values, stats could be extended to report it on both side.
On a clean installation, users might want to use server-state-file and
the recommended zero-warning option. This caused a problem if
server-state-file was not found, as a warning was emited, causing
startup to fail.
This will allow users to specify nonexistent server-state-file at first,
and dump states to the file later.
Fixes#2190
CF: Technically speaking, this patch can be backported to all stable
versions. But it is better to do so to 2.8 only for now.
Users might want to pre-create an empty file for later dumping
server-states. This commit allows for that by emiting a notice in case
file is empty and a warning if file is not empty, but version is unknown
Fix partially: #2190
CF: Technically speaking, this patch can be backported to all stable
versions. But it is better to do so to 2.8 only for now.
This puts an end to the occasional confusion between the "now" date
that is internal, monotonic and not synchronized with the system's
date, and "date" which is the system's date and not necessarily
monotonic. Variable "now" was removed and replaced with a 64-bit
integer "now_ns" which is a counter of nanoseconds. It wraps every
585 years, so if all goes well (i.e. if humanity does not need
haproxy anymore in 500 years), it will just never wrap. This implies
that now_ns is never nul and that the zero value can reliably be used
as "not set yet" for a timestamp if needed. This will also simplify
date checks where it becomes possible again to do "date1<date2".
All occurrences of "tv_to_ns(&now)" were simply replaced by "now_ns".
Due to the intricacies between now, global_now and now_offset, all 3
had to be turned to nanoseconds at once. It's not a problem since all
of them were solely used in 3 functions in clock.c, but they make the
patch look bigger than it really is.
The clock_update_local_date() and clock_update_global_date() functions
are now much simpler as there's no need anymore to perform conversions
nor to round the timeval up or down.
The wrapping continues to happen by presetting the internal offset in
the short future so that the 32-bit now_ms continues to wrap 20 seconds
after boot.
The start_time used to calculate uptime can still be turned to
nanoseconds now. One interrogation concerns global_now_ms which is used
only for the freq counters. It's unclear whether there's more value in
using two variables that need to be synchronized sequentially like today
or to just use global_now_ns divided by 1 million. Both approaches will
work equally well on modern systems, the difference might come from
smaller ones. Better not change anyhting for now.
One benefit of the new approach is that we now have an internal date
with a resolution of the nanosecond and the precision of the microsecond,
which can be useful to extend some measurements given that timestamps
also have this resolution.
Instead we're using ns_to_sec(tv_to_ns(&now)) which allows the tv_sec
part to disappear. At this point, "now" is only used as a timeval in
clock.c where it is updated.
This one is greatly inspired by "MINOR: server: change adm_st_chg_cause storage type".
While looking at current srv_op_st_chg_cause usage, it was clear that
the struct needed some cleanup since some leftovers from asynchronous server
state change updates were left behind and resulted in some useless code
duplication, and making the whole thing harder to maintain.
Two observations were made:
- by tracking down srv_set_{running, stopped, stopping} usage,
we can see that the <reason> argument is always a fixed statically
allocated string.
- check-related state change context (duration, status, code...) is
not used anymore since srv_append_status() directly extracts the
values from the server->check. This is pure legacy from when
the state changes were applied asynchronously.
To prevent code duplication, useless string copies and make the reason/cause
more exportable, we store it as an enum now, and we provide
srv_op_st_chg_cause() function to fetch the related description string.
HEALTH and AGENT causes (check related) are now explicitly identified to
make consumers like srv_append_op_chg_cause() able to fetch checks info
from the server itself if they need to.
When restoring from a state file: the server "Status" reports weird values on
the html stats page:
"5s UP" becomes -> "? UP" after the restore
This is due to a bug in srv_state_srv_update(): when restoring the states
from a state file, we rely on date.tv_sec to compute the process-relative
server last_change timestamp.
This is wrong because everywhere else we use now.tv_sec when dealing
with last_change, for instance in srv_update_status().
date (which is Wall clock time) deviates from now (monotonic time) in the
long run.
They should not be mixed, and given that last_change is an internal time value,
we should rely on now.tv_sec instead.
last_change export through "show servers state" cli is safe since we export
a delta and not the raw time value in dump_servers_state():
srv_time_since_last_change = now.tv_sec - srv->last_change
--
While this bug affects all stable versions, it was revealed in 2.8 thanks
to 28360dc ("MEDIUM: clock: force internal time to wrap early after boot")
This is due to the fact that "now" immediately deviates from "date",
whereas in the past they had the same value when starting.
Thus prior to 2.8 the bug is trickier since it could take some time for
date and now to deviate sufficiently for the issue to arise, and instead
of reporting absurd values that are easy to spot it could just result in
last_change becoming inconsistent over time.
As such, the fix should be backported to all stable versions.
[for 2.2 the patch needs to be applied manually since
srv_state_srv_update() was named srv_update_state() and can be found in
server.c instead of server_state.c]
Once in a while we get rid of this one. isblank() is missing on old
C libraries and only matches two values, so let's just replace it.
It was brought with this commit in 2.4:
0bf268e18 ("MINOR: server: Be more strict on the server-state line parsing")
It may be backported though it's really not important.
This change is required to support TCP/HTTP rules in defaults sections. The
'disabled' bitfield in the proxy structure, used to know if a proxy is
disabled or stopped, is replaced a generic bitfield named 'flags'.
PR_DISABLED and PR_STOPPED flags are renamed to PR_FL_DISABLED and
PR_FL_STOPPED respectively. In addition, everywhere there is a test to know
if a proxy is disabled or stopped, there is now a bitwise AND operation on
PR_FL_DISABLED and/or PR_FL_STOPPED flags.
This one has nothing to do with ssl_sock as it manipulates the struct
server only. Let's move it to server.c and remove unneeded dependencies
on ssl_sock.h. This further reduces by 10% the number of includes of
opensslconf.h and by 0.5% the number of compiled lines.
When a server relies on a SRV resolution, a task is created to clean it up
(fqdn/port and address) when the SRV resolution is considered as outdated
(based on the resolvers 'timeout' value). It is only possible if the server
inherits outdated info from a state file and is no longer selected to be
attached to a SRV item. Note that most of time, a server is attached to a
SRV item. Thus when the item becomes obsolete, the server is cleaned
up.
It is important to have such task to be sure the server will be free again
to have a chance to be resolved again with fresh information. Of course,
this patch is a workaround to solve a design issue. But there is no other
obvious way to fix it without rewritting all the resolvers part. And it must
be backportable.
This patch relies on following commits:
* MINOR: resolvers: Clean server in a dedicated function when removing a SRV item
* MINOR: resolvers: Remove server from named_servers tree when removing a SRV item
All the series must be backported as far as 2.2 after some observation
period. Backports to 2.0 and 1.8 must be evaluated.
When the state of a server is loaded, if there is no hostname defined for
this server and if a fqdn and a server record are retrieved from the state
file, it means the server should rely on a SRV resolution. But we must be
sure the server is configured this way. A SRV resolution must be configured
with the same SRV record. This part must be skipped if there is no SRV
resolution configured for this server or if the SRV record used is not the
same.
This patch should be backported as far as 1.8 after some observation period.
This patch add a ref into servers to register them onto the
record answer item used to set their hostnames.
It also adds a head list into 'srvrq' to register servers free
to be affected to a SRV record.
A head of a tree is also added to srvrq to put servers which
present a hotname in server state file. To re-link them fastly
to the matching record as soon an item present the same name.
This results in better performances on SRV record response
parsing.
This is an optimization but it could avoid to trigger the haproxy's
internal wathdog in some circumstances. And for this reason
it should be backported as far we can (2.0 ?)
The refactoring in commit 131b07be3 ("MEDIUM: server: Refactor
apply_server_state() to make it more readable") also had a copy-paste
error resulting in using global.server_state_file instead of the
function's argument, which easily crashes with a conf having a
state file in a backend and no global state file.
In addition, let's simplify the code and get rid of strcpy() which
almost certainly will break the build on OpenBSD.
This was introduced in 2.4-dev10, no backport is needed.
The refactoring in commit 131b07be3 ("MEDIUM: server: Refactor
apply_server_state() to make it more readable") made the global
server_state_base be dereferenced before being checked, resulting
in a crash on certain files.
This happened in 2.4-dev10, no backport is needed.
Recent changes on the server-state file loading have introduced a
regression. HAproxy crashes if a backend with no server-state file is
disabled in the configuration. Indeed, configuration of such backends is not
finalized. Thus many fields are not defined.
To fix the bug, disabled backends must be ignored. In addition a BUG_ON()
has been added to verify the proxy mode regarding the server-state file. It
must be specified (none, global or local) for enabled backends.
No backport needed.
