haproxy/include/proto/server.h
Willy Tarreau a0066ddbda MEDIUM: server: properly support and propagate the maintenance status
This change now involves a new flag SRV_ADMF_IMAINT to note that the
maintenance status of a server is inherited from another server. Thus,
we know at each server level in the chain if it's running, in forced
maintenance or in a maintenance status because it tracks another server,
or even in both states.

Disabling a server propagates this flag down to other servers. Enabling
a server flushes the flag down. A server becomes up again once both of
its flags are cleared.

Two new functions "srv_adm_set_maint()" and "srv_adm_set_ready()" are used to
manipulate this maintenance status. They're used by the CLI and the stats
page.

Now the stats page always says "MAINT" instead of "MAINT(via)" and it's
only the chk/down field which reports "via x/y" when the status is
inherited from another server, but it doesn't say it when a server was
forced into maintenance. The CSV output indicates "MAINT (via x/y)"
instead of only "MAINT(via)". This is the most accurate representation.

One important thing is that now entering/leaving maintenance for a
tracking server correctly follows the state of the tracked server.
2014-05-22 11:27:00 +02:00

151 lines
5.3 KiB
C

/*
* include/proto/server.h
* This file defines everything related to servers.
*
* Copyright (C) 2000-2009 Willy Tarreau - w@1wt.eu
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation, version 2.1
* exclusively.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef _PROTO_SERVER_H
#define _PROTO_SERVER_H
#include <unistd.h>
#include <common/config.h>
#include <common/time.h>
#include <types/proxy.h>
#include <types/queue.h>
#include <types/server.h>
#include <proto/queue.h>
#include <proto/log.h>
#include <proto/freq_ctr.h>
int srv_downtime(const struct server *s);
int srv_lastsession(const struct server *s);
int srv_getinter(const struct check *check);
int parse_server(const char *file, int linenum, char **args, struct proxy *curproxy, struct proxy *defproxy);
/* increase the number of cumulated connections on the designated server */
static void inline srv_inc_sess_ctr(struct server *s)
{
s->counters.cum_sess++;
update_freq_ctr(&s->sess_per_sec, 1);
if (s->sess_per_sec.curr_ctr > s->counters.sps_max)
s->counters.sps_max = s->sess_per_sec.curr_ctr;
}
/* set the time of last session on the designated server */
static void inline srv_set_sess_last(struct server *s)
{
s->counters.last_sess = now.tv_sec;
}
#endif /* _PROTO_SERVER_H */
/*
* Registers the server keyword list <kwl> as a list of valid keywords for next
* parsing sessions.
*/
void srv_register_keywords(struct srv_kw_list *kwl);
/* Return a pointer to the server keyword <kw>, or NULL if not found. */
struct srv_kw *srv_find_kw(const char *kw);
/* Dumps all registered "server" keywords to the <out> string pointer. */
void srv_dump_kws(char **out);
/* Recomputes the server's eweight based on its state, uweight, the current time,
* and the proxy's algorihtm. To be used after updating sv->uweight. The warmup
* state is automatically disabled if the time is elapsed.
*/
void server_recalc_eweight(struct server *sv);
/* returns the current server throttle rate between 0 and 100% */
static inline unsigned int server_throttle_rate(struct server *sv)
{
struct proxy *px = sv->proxy;
/* when uweight is 0, we're in soft-stop so that cannot be a slowstart,
* thus the throttle is 100%.
*/
if (!sv->uweight)
return 100;
return (100U * px->lbprm.wmult * sv->eweight + px->lbprm.wdiv - 1) / (px->lbprm.wdiv * sv->uweight);
}
/*
* Parses weight_str and configures sv accordingly.
* Returns NULL on success, error message string otherwise.
*/
const char *server_parse_weight_change_request(struct server *sv,
const char *weight_str);
/*
* Return true if the server has a zero user-weight, meaning it's in draining
* mode (ie: not taking new non-persistent connections).
*/
static inline int server_is_draining(const struct server *s)
{
return !s->uweight;
}
/* Shutdown all connections of a server. The caller must pass a termination
* code in <why>, which must be one of SN_ERR_* indicating the reason for the
* shutdown.
*/
void srv_shutdown_sessions(struct server *srv, int why);
/* Shutdown all connections of all backup servers of a proxy. The caller must
* pass a termination code in <why>, which must be one of SN_ERR_* indicating
* the reason for the shutdown.
*/
void srv_shutdown_backup_sessions(struct proxy *px, int why);
/* Appends some information to a message string related to a server going UP or DOWN.
* If <forced> is null and the server tracks another one, a "via" information will
* be provided to know where the status came from. If xferred is non-negative, some
* information about requeued sessions are provided.
*/
void srv_adm_append_status(struct chunk *msg, struct server *s, int xferred, int forced);
/* Puts server <s> into maintenance mode, and propagate that status down to all
* tracking servers. This does the same action as the CLI's "disable server x".
* A log is emitted for all servers that were not yet in maintenance mode.
* Health checks are disabled but not agent checks. The server is marked as
* being either forced into maintenance by having <mode> set to SRV_ADMF_FMAINT,
* or as inheriting the maintenance status by having <mode> set to
* SRV_ADMF_IMAINT. Nothing is done if neither flag is set.
*/
void srv_adm_set_maint(struct server *s, enum srv_admin mode);
/* Gets server <s> out of maintenance mode, and propagate that status down to
* all tracking servers. This does the same action as the CLI's "enable server x".
* A log is emitted for all servers that leave maintenance mode. Health checks
* are possibly enabled again. The server is marked as leaving forced maintenance
* when <mode> is set to SRV_ADMF_FMAINT, or as leaving inherited maintenance
* when <mode> set to SRV_ADMF_IMAINT. Nothing is done if neither flag is set.
*/
void srv_adm_set_ready(struct server *s, enum srv_admin mode);
/*
* Local variables:
* c-indent-level: 8
* c-basic-offset: 8
* End:
*/