blob: 40fb698ef9fb786ee194b995fb18d61660490301 [file] [log] [blame]
/*
* Health-checks functions.
*
* Copyright 2000-2009 Willy Tarreau <w@1wt.eu>
* Copyright 2007-2008 Krzysztof Piotr Oledzki <ole@ans.pl>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
*/
#include <assert.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <arpa/inet.h>
#include <common/compat.h>
#include <common/config.h>
#include <common/mini-clist.h>
#include <common/standard.h>
#include <common/time.h>
#include <types/global.h>
#include <proto/backend.h>
#include <proto/buffers.h>
#include <proto/fd.h>
#include <proto/log.h>
#include <proto/queue.h>
#include <proto/port_range.h>
#include <proto/proto_http.h>
#include <proto/proto_tcp.h>
#include <proto/proxy.h>
#include <proto/server.h>
#include <proto/task.h>
/* sends a log message when a backend goes down, and also sets last
* change date.
*/
static void set_backend_down(struct proxy *be)
{
be->last_change = now.tv_sec;
be->down_trans++;
Alert("%s '%s' has no server available!\n", proxy_type_str(be), be->id);
send_log(be, LOG_EMERG, "%s %s has no server available!\n", proxy_type_str(be), be->id);
}
/* Redistribute pending connections when a server goes down. The number of
* connections redistributed is returned.
*/
static int redistribute_pending(struct server *s)
{
struct pendconn *pc, *pc_bck, *pc_end;
int xferred = 0;
FOREACH_ITEM_SAFE(pc, pc_bck, &s->pendconns, pc_end, struct pendconn *, list) {
struct session *sess = pc->sess;
if (sess->be->options & PR_O_REDISP) {
/* The REDISP option was specified. We will ignore
* cookie and force to balance or use the dispatcher.
*/
/* it's left to the dispatcher to choose a server */
sess->flags &= ~(SN_DIRECT | SN_ASSIGNED | SN_ADDR_SET);
pendconn_free(pc);
task_wakeup(sess->task, TASK_WOKEN_RES);
xferred++;
}
}
return xferred;
}
/* Check for pending connections at the backend, and assign some of them to
* the server coming up. The server's weight is checked before being assigned
* connections it may not be able to handle. The total number of transferred
* connections is returned.
*/
static int check_for_pending(struct server *s)
{
int xferred;
if (!s->eweight)
return 0;
for (xferred = 0; !s->maxconn || xferred < srv_dynamic_maxconn(s); xferred++) {
struct session *sess;
struct pendconn *p;
p = pendconn_from_px(s->proxy);
if (!p)
break;
p->sess->srv = s;
sess = p->sess;
pendconn_free(p);
task_wakeup(sess->task, TASK_WOKEN_RES);
}
return xferred;
}
/* Sets server <s> down, notifies by all available means, recounts the
* remaining servers on the proxy and transfers queued sessions whenever
* possible to other servers. It automatically recomputes the number of
* servers, but not the map.
*/
static void set_server_down(struct server *s)
{
struct server *srv;
struct chunk msg;
int xferred;
if (s->health == s->rise || s->tracked) {
int srv_was_paused = s->state & SRV_GOINGDOWN;
s->last_change = now.tv_sec;
s->state &= ~(SRV_RUNNING | SRV_GOINGDOWN);
s->proxy->lbprm.set_server_status_down(s);
/* we might have sessions queued on this server and waiting for
* a connection. Those which are redispatchable will be queued
* to another server or to the proxy itself.
*/
xferred = redistribute_pending(s);
msg.len = 0;
msg.str = trash;
chunk_printf(&msg, sizeof(trash),
"%sServer %s/%s is DOWN", s->state & SRV_BACKUP ? "Backup " : "",
s->proxy->id, s->id);
if (s->tracked)
chunk_printf(&msg, sizeof(trash), " via %s/%s",
s->tracked->proxy->id, s->tracked->id);
chunk_printf(&msg, sizeof(trash), ". %d active and %d backup servers left.%s"
" %d sessions active, %d requeued, %d remaining in queue.\n",
s->proxy->srv_act, s->proxy->srv_bck,
(s->proxy->srv_bck && !s->proxy->srv_act) ? " Running on backup." : "",
s->cur_sess, xferred, s->nbpend);
Warning("%s", trash);
/* we don't send an alert if the server was previously paused */
if (srv_was_paused)
send_log(s->proxy, LOG_NOTICE, "%s", trash);
else
send_log(s->proxy, LOG_ALERT, "%s", trash);
if (s->proxy->srv_bck == 0 && s->proxy->srv_act == 0)
set_backend_down(s->proxy);
s->down_trans++;
if (s->state & SRV_CHECKED)
for(srv = s->tracknext; srv; srv = srv->tracknext)
set_server_down(srv);
}
s->health = 0; /* failure */
}
static void set_server_up(struct server *s) {
struct server *srv;
struct chunk msg;
int xferred;
if (s->health == s->rise || s->tracked) {
if (s->proxy->srv_bck == 0 && s->proxy->srv_act == 0) {
if (s->proxy->last_change < now.tv_sec) // ignore negative times
s->proxy->down_time += now.tv_sec - s->proxy->last_change;
s->proxy->last_change = now.tv_sec;
}
if (s->last_change < now.tv_sec) // ignore negative times
s->down_time += now.tv_sec - s->last_change;
s->last_change = now.tv_sec;
s->state |= SRV_RUNNING;
if (s->slowstart > 0) {
s->state |= SRV_WARMINGUP;
if (s->proxy->lbprm.algo & BE_LB_PROP_DYN) {
/* For dynamic algorithms, start at the first step of the weight,
* without multiplying by BE_WEIGHT_SCALE.
*/
s->eweight = s->uweight;
if (s->proxy->lbprm.update_server_eweight)
s->proxy->lbprm.update_server_eweight(s);
}
}
s->proxy->lbprm.set_server_status_up(s);
/* check if we can handle some connections queued at the proxy. We
* will take as many as we can handle.
*/
xferred = check_for_pending(s);
msg.len = 0;
msg.str = trash;
chunk_printf(&msg, sizeof(trash),
"%sServer %s/%s is UP", s->state & SRV_BACKUP ? "Backup " : "",
s->proxy->id, s->id);
if (s->tracked)
chunk_printf(&msg, sizeof(trash), " via %s/%s",
s->tracked->proxy->id, s->tracked->id);
chunk_printf(&msg, sizeof(trash), ". %d active and %d backup servers online.%s"
" %d sessions requeued, %d total in queue.\n",
s->proxy->srv_act, s->proxy->srv_bck,
(s->proxy->srv_bck && !s->proxy->srv_act) ? " Running on backup." : "",
xferred, s->nbpend);
Warning("%s", trash);
send_log(s->proxy, LOG_NOTICE, "%s", trash);
if (s->state & SRV_CHECKED)
for(srv = s->tracknext; srv; srv = srv->tracknext)
set_server_up(srv);
}
if (s->health >= s->rise)
s->health = s->rise + s->fall - 1; /* OK now */
}
static void set_server_disabled(struct server *s) {
struct server *srv;
struct chunk msg;
int xferred;
s->state |= SRV_GOINGDOWN;
s->proxy->lbprm.set_server_status_down(s);
/* we might have sessions queued on this server and waiting for
* a connection. Those which are redispatchable will be queued
* to another server or to the proxy itself.
*/
xferred = redistribute_pending(s);
msg.len = 0;
msg.str = trash;
chunk_printf(&msg, sizeof(trash),
"Load-balancing on %sServer %s/%s is disabled",
s->state & SRV_BACKUP ? "Backup " : "",
s->proxy->id, s->id);
if (s->tracked)
chunk_printf(&msg, sizeof(trash), " via %s/%s",
s->tracked->proxy->id, s->tracked->id);
chunk_printf(&msg, sizeof(trash),". %d active and %d backup servers online.%s"
" %d sessions requeued, %d total in queue.\n",
s->proxy->srv_act, s->proxy->srv_bck,
(s->proxy->srv_bck && !s->proxy->srv_act) ? " Running on backup." : "",
xferred, s->nbpend);
Warning("%s", trash);
send_log(s->proxy, LOG_NOTICE, "%s", trash);
if (!s->proxy->srv_bck && !s->proxy->srv_act)
set_backend_down(s->proxy);
if (s->state & SRV_CHECKED)
for(srv = s->tracknext; srv; srv = srv->tracknext)
set_server_disabled(srv);
}
static void set_server_enabled(struct server *s) {
struct server *srv;
struct chunk msg;
int xferred;
s->state &= ~SRV_GOINGDOWN;
s->proxy->lbprm.set_server_status_up(s);
/* check if we can handle some connections queued at the proxy. We
* will take as many as we can handle.
*/
xferred = check_for_pending(s);
msg.len = 0;
msg.str = trash;
chunk_printf(&msg, sizeof(trash),
"Load-balancing on %sServer %s/%s is enabled again",
s->state & SRV_BACKUP ? "Backup " : "",
s->proxy->id, s->id);
if (s->tracked)
chunk_printf(&msg, sizeof(trash), " via %s/%s",
s->tracked->proxy->id, s->tracked->id);
chunk_printf(&msg, sizeof(trash), ". %d active and %d backup servers online.%s"
" %d sessions requeued, %d total in queue.\n",
s->proxy->srv_act, s->proxy->srv_bck,
(s->proxy->srv_bck && !s->proxy->srv_act) ? " Running on backup." : "",
xferred, s->nbpend);
Warning("%s", trash);
send_log(s->proxy, LOG_NOTICE, "%s", trash);
if (s->state & SRV_CHECKED)
for(srv = s->tracknext; srv; srv = srv->tracknext)
set_server_enabled(srv);
}
/*
* This function is used only for server health-checks. It handles
* the connection acknowledgement. If the proxy requires HTTP health-checks,
* it sends the request. In other cases, it fills s->result with SRV_CHK_*.
* The function itself returns 0 if it needs some polling before being called
* again, otherwise 1.
*/
static int event_srv_chk_w(int fd)
{
__label__ out_wakeup, out_nowake, out_poll, out_error;
struct task *t = fdtab[fd].owner;
struct server *s = t->context;
//fprintf(stderr, "event_srv_chk_w, state=%ld\n", unlikely(fdtab[fd].state));
if (unlikely(fdtab[fd].state == FD_STERROR || (fdtab[fd].ev & FD_POLL_ERR)))
goto out_error;
/* here, we know that the connection is established */
if (!(s->result & SRV_CHK_ERROR)) {
/* we don't want to mark 'UP' a server on which we detected an error earlier */
if ((s->proxy->options & PR_O_HTTP_CHK) ||
(s->proxy->options & PR_O_SSL3_CHK) ||
(s->proxy->options & PR_O_SMTP_CHK)) {
int ret;
/* we want to check if this host replies to HTTP or SSLv3 requests
* so we'll send the request, and won't wake the checker up now.
*/
if (s->proxy->options & PR_O_SSL3_CHK) {
/* SSL requires that we put Unix time in the request */
int gmt_time = htonl(date.tv_sec);
memcpy(s->proxy->check_req + 11, &gmt_time, 4);
}
#ifndef MSG_NOSIGNAL
ret = send(fd, s->proxy->check_req, s->proxy->check_len, MSG_DONTWAIT);
#else
ret = send(fd, s->proxy->check_req, s->proxy->check_len, MSG_DONTWAIT | MSG_NOSIGNAL);
#endif
if (ret == s->proxy->check_len) {
/* we allow up to <timeout.check> if nonzero for a responce */
if (s->proxy->timeout.check)
t->expire = tick_add_ifset(now_ms, s->proxy->timeout.check);
EV_FD_SET(fd, DIR_RD); /* prepare for reading reply */
goto out_nowake;
}
else if (ret == 0 || errno == EAGAIN)
goto out_poll;
else
goto out_error;
}
else {
/* We have no data to send to check the connection, and
* getsockopt() will not inform us whether the connection
* is still pending. So we'll reuse connect() to check the
* state of the socket. This has the advantage of givig us
* the following info :
* - error
* - connecting (EALREADY, EINPROGRESS)
* - connected (EISCONN, 0)
*/
struct sockaddr_in sa;
sa = (s->check_addr.sin_addr.s_addr) ? s->check_addr : s->addr;
sa.sin_port = htons(s->check_port);
if (connect(fd, (struct sockaddr *)&sa, sizeof(sa)) == 0)
errno = 0;
if (errno == EALREADY || errno == EINPROGRESS)
goto out_poll;
if (errno && errno != EISCONN)
goto out_error;
/* good TCP connection is enough */
s->result |= SRV_CHK_RUNNING;
goto out_wakeup;
}
}
out_wakeup:
task_wakeup(t, TASK_WOKEN_IO);
out_nowake:
EV_FD_CLR(fd, DIR_WR); /* nothing more to write */
fdtab[fd].ev &= ~FD_POLL_OUT;
return 1;
out_poll:
/* The connection is still pending. We'll have to poll it
* before attempting to go further. */
fdtab[fd].ev &= ~FD_POLL_OUT;
return 0;
out_error:
s->result |= SRV_CHK_ERROR;
fdtab[fd].state = FD_STERROR;
goto out_wakeup;
}
/*
* This function is used only for server health-checks. It handles the server's
* reply to an HTTP request or SSL HELLO. It sets s->result to SRV_CHK_RUNNING
* if an HTTP server replies HTTP 2xx or 3xx (valid responses), if an SMTP
* server returns 2xx, or if an SSL server returns at least 5 bytes in response
* to an SSL HELLO (the principle is that this is enough to distinguish between
* an SSL server and a pure TCP relay). All other cases will set s->result to
* SRV_CHK_ERROR. The function returns 0 if it needs to be called again after
* some polling, otherwise non-zero..
*/
static int event_srv_chk_r(int fd)
{
__label__ out_wakeup;
int len;
struct task *t = fdtab[fd].owner;
struct server *s = t->context;
int skerr;
socklen_t lskerr = sizeof(skerr);
len = -1;
if (unlikely((s->result & SRV_CHK_ERROR) ||
(fdtab[fd].state == FD_STERROR) ||
(fdtab[fd].ev & FD_POLL_ERR) ||
(getsockopt(fd, SOL_SOCKET, SO_ERROR, &skerr, &lskerr) == -1) ||
(skerr != 0))) {
/* in case of TCP only, this tells us if the connection failed */
s->result |= SRV_CHK_ERROR;
goto out_wakeup;
}
#ifndef MSG_NOSIGNAL
len = recv(fd, trash, sizeof(trash), 0);
#else
/* Warning! Linux returns EAGAIN on SO_ERROR if data are still available
* but the connection was closed on the remote end. Fortunately, recv still
* works correctly and we don't need to do the getsockopt() on linux.
*/
len = recv(fd, trash, sizeof(trash), MSG_NOSIGNAL);
#endif
if (unlikely(len < 0 && errno == EAGAIN)) {
/* we want some polling to happen first */
fdtab[fd].ev &= ~FD_POLL_IN;
return 0;
}
/* Note: the response will only be accepted if read at once */
if (s->proxy->options & PR_O_HTTP_CHK) {
/* Check if the server speaks HTTP 1.X */
if ((len < strlen("HTTP/1.0 000\r")) ||
(memcmp(trash, "HTTP/1.", 7) != 0)) {
s->result |= SRV_CHK_ERROR;
goto out_wakeup;
}
/* check the reply : HTTP/1.X 2xx and 3xx are OK */
if (trash[9] == '2' || trash[9] == '3')
s->result |= SRV_CHK_RUNNING;
else if ((s->proxy->options & PR_O_DISABLE404) &&
(s->state & SRV_RUNNING) &&
(memcmp(&trash[9], "404", 3) == 0)) {
/* 404 may be accepted as "stopping" only if the server was up */
s->result |= SRV_CHK_RUNNING | SRV_CHK_DISABLE;
}
else
s->result |= SRV_CHK_ERROR;
}
else if (s->proxy->options & PR_O_SSL3_CHK) {
/* Check for SSLv3 alert or handshake */
if ((len >= 5) && (trash[0] == 0x15 || trash[0] == 0x16))
s->result |= SRV_CHK_RUNNING;
else
s->result |= SRV_CHK_ERROR;
}
else if (s->proxy->options & PR_O_SMTP_CHK) {
/* Check for SMTP code 2xx (should be 250) */
if ((len >= 3) && (trash[0] == '2'))
s->result |= SRV_CHK_RUNNING;
else
s->result |= SRV_CHK_ERROR;
}
else {
/* other checks are valid if the connection succeeded anyway */
s->result |= SRV_CHK_RUNNING;
}
out_wakeup:
if (s->result & SRV_CHK_ERROR)
fdtab[fd].state = FD_STERROR;
EV_FD_CLR(fd, DIR_RD);
task_wakeup(t, TASK_WOKEN_IO);
fdtab[fd].ev &= ~FD_POLL_IN;
return 1;
}
/*
* manages a server health-check. Returns
* the time the task accepts to wait, or TIME_ETERNITY for infinity.
*/
struct task *process_chk(struct task *t)
{
int attempts = 0;
struct server *s = t->context;
struct sockaddr_in sa;
int fd;
int rv;
//fprintf(stderr, "process_chk: task=%p\n", t);
new_chk:
if (attempts++ > 0) {
/* we always fail to create a server, let's stop insisting... */
while (tick_is_expired(t->expire, now_ms))
t->expire = tick_add(t->expire, MS_TO_TICKS(s->inter));
return t;
}
fd = s->curfd;
if (fd < 0) { /* no check currently running */
//fprintf(stderr, "process_chk: 2\n");
if (!tick_is_expired(t->expire, now_ms)) /* woke up too early */
return t;
/* we don't send any health-checks when the proxy is stopped or when
* the server should not be checked.
*/
if (!(s->state & SRV_CHECKED) || s->proxy->state == PR_STSTOPPED) {
while (tick_is_expired(t->expire, now_ms))
t->expire = tick_add(t->expire, MS_TO_TICKS(s->inter));
return t;
}
/* we'll initiate a new check */
s->result = SRV_CHK_UNKNOWN; /* no result yet */
if ((fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) != -1) {
if ((fd < global.maxsock) &&
(fcntl(fd, F_SETFL, O_NONBLOCK) != -1) &&
(setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, (char *) &one, sizeof(one)) != -1)) {
//fprintf(stderr, "process_chk: 3\n");
if (s->proxy->options & PR_O_TCP_NOLING) {
/* We don't want to useless data */
setsockopt(fd, SOL_SOCKET, SO_LINGER, (struct linger *) &nolinger, sizeof(struct linger));
}
if (s->check_addr.sin_addr.s_addr)
/* we'll connect to the check addr specified on the server */
sa = s->check_addr;
else
/* we'll connect to the addr on the server */
sa = s->addr;
/* we'll connect to the check port on the server */
sa.sin_port = htons(s->check_port);
/* allow specific binding :
* - server-specific at first
* - proxy-specific next
*/
if (s->state & SRV_BIND_SRC) {
struct sockaddr_in *remote = NULL;
int ret, flags = 0;
#if defined(CONFIG_HAP_CTTPROXY) || defined(CONFIG_HAP_LINUX_TPROXY)
if ((s->state & SRV_TPROXY_MASK) == SRV_TPROXY_ADDR) {
remote = (struct sockaddr_in *)&s->tproxy_addr;
flags = 3;
}
#endif
#ifdef SO_BINDTODEVICE
/* Note: this might fail if not CAP_NET_RAW */
if (s->iface_name)
setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE,
s->iface_name, s->iface_len + 1);
#endif
if (s->sport_range) {
int bind_attempts = 10; /* should be more than enough to find a spare port */
struct sockaddr_in src;
ret = 1;
src = s->source_addr;
do {
/* note: in case of retry, we may have to release a previously
* allocated port, hence this loop's construct.
*/
port_range_release_port(fdtab[fd].port_range, fdtab[fd].local_port);
fdtab[fd].port_range = NULL;
if (!bind_attempts)
break;
bind_attempts--;
fdtab[fd].local_port = port_range_alloc_port(s->sport_range);
if (!fdtab[fd].local_port)
break;
fdtab[fd].port_range = s->sport_range;
src.sin_port = htons(fdtab[fd].local_port);
ret = tcpv4_bind_socket(fd, flags, &src, remote);
} while (ret != 0); /* binding NOK */
}
else {
ret = tcpv4_bind_socket(fd, flags, &s->source_addr, remote);
}
if (ret) {
s->result |= SRV_CHK_ERROR;
switch (ret) {
case 1:
Alert("Cannot bind to source address before connect() for server %s/%s. Aborting.\n",
s->proxy->id, s->id);
break;
case 2:
Alert("Cannot bind to tproxy source address before connect() for server %s/%s. Aborting.\n",
s->proxy->id, s->id);
break;
}
}
}
else if (s->proxy->options & PR_O_BIND_SRC) {
struct sockaddr_in *remote = NULL;
int ret, flags = 0;
#if defined(CONFIG_HAP_CTTPROXY) || defined(CONFIG_HAP_LINUX_TPROXY)
if ((s->proxy->options & PR_O_TPXY_MASK) == PR_O_TPXY_ADDR) {
remote = (struct sockaddr_in *)&s->proxy->tproxy_addr;
flags = 3;
}
#endif
#ifdef SO_BINDTODEVICE
/* Note: this might fail if not CAP_NET_RAW */
if (s->proxy->iface_name)
setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE,
s->proxy->iface_name, s->proxy->iface_len + 1);
#endif
ret = tcpv4_bind_socket(fd, flags, &s->proxy->source_addr, remote);
if (ret) {
s->result |= SRV_CHK_ERROR;
switch (ret) {
case 1:
Alert("Cannot bind to source address before connect() for %s '%s'. Aborting.\n",
proxy_type_str(s->proxy), s->proxy->id);
break;
case 2:
Alert("Cannot bind to tproxy source address before connect() for %s '%s'. Aborting.\n",
proxy_type_str(s->proxy), s->proxy->id);
break;
}
}
}
if (s->result == SRV_CHK_UNKNOWN) {
#ifdef TCP_QUICKACK
/* disabling tcp quick ack now allows
* the request to leave the machine with
* the first ACK.
*/
if (s->proxy->options2 & PR_O2_SMARTCON)
setsockopt(fd, SOL_TCP, TCP_QUICKACK, (char *) &zero, sizeof(zero));
#endif
if ((connect(fd, (struct sockaddr *)&sa, sizeof(sa)) != -1) || (errno == EINPROGRESS)) {
/* OK, connection in progress or established */
//fprintf(stderr, "process_chk: 4\n");
s->curfd = fd; /* that's how we know a test is in progress ;-) */
fd_insert(fd);
fdtab[fd].owner = t;
fdtab[fd].cb[DIR_RD].f = &event_srv_chk_r;
fdtab[fd].cb[DIR_RD].b = NULL;
fdtab[fd].cb[DIR_WR].f = &event_srv_chk_w;
fdtab[fd].cb[DIR_WR].b = NULL;
fdtab[fd].peeraddr = (struct sockaddr *)&sa;
fdtab[fd].peerlen = sizeof(sa);
fdtab[fd].state = FD_STCONN; /* connection in progress */
fdtab[fd].flags = FD_FL_TCP | FD_FL_TCP_NODELAY;
EV_FD_SET(fd, DIR_WR); /* for connect status */
#ifdef DEBUG_FULL
assert (!EV_FD_ISSET(fd, DIR_RD));
#endif
//fprintf(stderr, "process_chk: 4+, %lu\n", __tv_to_ms(&s->proxy->timeout.connect));
/* we allow up to min(inter, timeout.connect) for a connection
* to establish but only when timeout.check is set
* as it may be to short for a full check otherwise
*/
t->expire = tick_add(now_ms, MS_TO_TICKS(s->inter));
if (s->proxy->timeout.check && s->proxy->timeout.connect) {
int t_con = tick_add(now_ms, s->proxy->timeout.connect);
t->expire = tick_first(t->expire, t_con);
}
return t;
}
else if (errno != EALREADY && errno != EISCONN && errno != EAGAIN) {
s->result |= SRV_CHK_ERROR; /* a real error */
}
}
}
port_range_release_port(fdtab[fd].port_range, fdtab[fd].local_port);
fdtab[fd].port_range = NULL;
close(fd); /* socket creation error */
}
if (s->result == SRV_CHK_UNKNOWN) { /* nothing done */
//fprintf(stderr, "process_chk: 6\n");
while (tick_is_expired(t->expire, now_ms))
t->expire = tick_add(t->expire, MS_TO_TICKS(s->inter));
goto new_chk; /* may be we should initialize a new check */
}
/* here, we have seen a failure */
if (s->health > s->rise) {
s->health--; /* still good */
s->failed_checks++;
}
else
set_server_down(s);
//fprintf(stderr, "process_chk: 7, %lu\n", __tv_to_ms(&s->proxy->timeout.connect));
/* we allow up to min(inter, timeout.connect) for a connection
* to establish but only when timeout.check is set
* as it may be to short for a full check otherwise
*/
while (tick_is_expired(t->expire, now_ms)) {
int t_con;
t_con = tick_add(t->expire, s->proxy->timeout.connect);
t->expire = tick_add(t->expire, MS_TO_TICKS(s->inter));
if (s->proxy->timeout.check)
t->expire = tick_first(t->expire, t_con);
}
goto new_chk;
}
else {
//fprintf(stderr, "process_chk: 8\n");
/* there was a test running */
if ((s->result & (SRV_CHK_ERROR|SRV_CHK_RUNNING)) == SRV_CHK_RUNNING) { /* good server detected */
//fprintf(stderr, "process_chk: 9\n");
if (s->state & SRV_WARMINGUP) {
if (now.tv_sec < s->last_change || now.tv_sec >= s->last_change + s->slowstart) {
s->state &= ~SRV_WARMINGUP;
if (s->proxy->lbprm.algo & BE_LB_PROP_DYN)
s->eweight = s->uweight * BE_WEIGHT_SCALE;
if (s->proxy->lbprm.update_server_eweight)
s->proxy->lbprm.update_server_eweight(s);
}
else if (s->proxy->lbprm.algo & BE_LB_PROP_DYN) {
/* for dynamic algorithms, let's update the weight */
s->eweight = (BE_WEIGHT_SCALE * (now.tv_sec - s->last_change) +
s->slowstart - 1) / s->slowstart;
s->eweight *= s->uweight;
if (s->proxy->lbprm.update_server_eweight)
s->proxy->lbprm.update_server_eweight(s);
}
/* probably that we can refill this server with a bit more connections */
check_for_pending(s);
}
/* we may have to add/remove this server from the LB group */
if ((s->state & SRV_RUNNING) && (s->proxy->options & PR_O_DISABLE404)) {
if ((s->state & SRV_GOINGDOWN) &&
((s->result & (SRV_CHK_RUNNING|SRV_CHK_DISABLE)) == SRV_CHK_RUNNING))
set_server_enabled(s);
else if (!(s->state & SRV_GOINGDOWN) &&
((s->result & (SRV_CHK_RUNNING | SRV_CHK_DISABLE)) ==
(SRV_CHK_RUNNING | SRV_CHK_DISABLE)))
set_server_disabled(s);
}
if (s->health < s->rise + s->fall - 1) {
s->health++; /* was bad, stays for a while */
set_server_up(s);
}
s->curfd = -1; /* no check running anymore */
fd_delete(fd);
rv = 0;
if (global.spread_checks > 0) {
rv = srv_getinter(s) * global.spread_checks / 100;
rv -= (int) (2 * rv * (rand() / (RAND_MAX + 1.0)));
//fprintf(stderr, "process_chk(%p): (%d+/-%d%%) random=%d\n", s, srv_getinter(s), global.spread_checks, rv);
}
t->expire = tick_add(now_ms, MS_TO_TICKS(srv_getinter(s) + rv));
goto new_chk;
}
else if ((s->result & SRV_CHK_ERROR) || tick_is_expired(t->expire, now_ms)) {
//fprintf(stderr, "process_chk: 10\n");
/* failure or timeout detected */
if (s->health > s->rise) {
s->health--; /* still good */
s->failed_checks++;
}
else
set_server_down(s);
s->curfd = -1;
fd_delete(fd);
rv = 0;
if (global.spread_checks > 0) {
rv = srv_getinter(s) * global.spread_checks / 100;
rv -= (int) (2 * rv * (rand() / (RAND_MAX + 1.0)));
//fprintf(stderr, "process_chk(%p): (%d+/-%d%%) random=%d\n", s, srv_getinter(s), global.spread_checks, rv);
}
t->expire = tick_add(now_ms, MS_TO_TICKS(srv_getinter(s) + rv));
goto new_chk;
}
/* if result is unknown and there's no timeout, we have to wait again */
}
//fprintf(stderr, "process_chk: 11\n");
s->result = SRV_CHK_UNKNOWN;
return t;
}
/*
* Start health-check.
* Returns 0 if OK, -1 if error, and prints the error in this case.
*/
int start_checks() {
struct proxy *px;
struct server *s;
struct task *t;
int nbchk=0, mininter=0, srvpos=0;
/* 1- count the checkers to run simultaneously.
* We also determine the minimum interval among all of those which
* have an interval larger than SRV_CHK_INTER_THRES. This interval
* will be used to spread their start-up date. Those which have
* a shorter interval will start independantly and will not dictate
* too short an interval for all others.
*/
for (px = proxy; px; px = px->next) {
for (s = px->srv; s; s = s->next) {
if (!(s->state & SRV_CHECKED))
continue;
if ((srv_getinter(s) >= SRV_CHK_INTER_THRES) &&
(!mininter || mininter > srv_getinter(s)))
mininter = srv_getinter(s);
nbchk++;
}
}
if (!nbchk)
return 0;
srand((unsigned)time(NULL));
/*
* 2- start them as far as possible from each others. For this, we will
* start them after their interval set to the min interval divided by
* the number of servers, weighted by the server's position in the list.
*/
for (px = proxy; px; px = px->next) {
for (s = px->srv; s; s = s->next) {
if (!(s->state & SRV_CHECKED))
continue;
if ((t = task_new()) == NULL) {
Alert("Starting [%s:%s] check: out of memory.\n", px->id, s->id);
return -1;
}
s->check = t;
t->process = process_chk;
t->context = s;
/* check this every ms */
t->expire = tick_add(now_ms,
MS_TO_TICKS(((mininter && mininter >= srv_getinter(s)) ?
mininter : srv_getinter(s)) * srvpos / nbchk));
task_queue(t);
srvpos++;
}
}
return 0;
}
/*
* Local variables:
* c-indent-level: 8
* c-basic-offset: 8
* End:
*/