diff options
Diffstat (limited to 'source4/cluster/ctdb/takeover/ctdb_takeover.c')
| -rw-r--r-- | source4/cluster/ctdb/takeover/ctdb_takeover.c | 583 |
1 files changed, 583 insertions, 0 deletions
diff --git a/source4/cluster/ctdb/takeover/ctdb_takeover.c b/source4/cluster/ctdb/takeover/ctdb_takeover.c new file mode 100644 index 0000000000..862382d90a --- /dev/null +++ b/source4/cluster/ctdb/takeover/ctdb_takeover.c @@ -0,0 +1,583 @@ +/* + ctdb recovery code + + Copyright (C) Ronnie Sahlberg 2007 + Copyright (C) Andrew Tridgell 2007 + + 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; either + version 3 of the License, or (at your option) any later version. + + 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, see <http://www.gnu.org/licenses/>. +*/ +#include "includes.h" +#include "lib/events/events.h" +#include "lib/tdb/include/tdb.h" +#include "system/network.h" +#include "system/filesys.h" +#include "system/wait.h" +#include "../include/ctdb_private.h" + + +#define TAKEOVER_TIMEOUT() timeval_current_ofs(5,0) + +#define CTDB_ARP_INTERVAL 1 +#define CTDB_ARP_REPEAT 3 + +struct ctdb_takeover_arp { + struct ctdb_context *ctdb; + uint32_t count; + struct sockaddr_in sin; + struct ctdb_tcp_list *tcp_list; +}; + +/* + lists of tcp endpoints + */ +struct ctdb_tcp_list { + struct ctdb_tcp_list *prev, *next; + uint32_t vnn; + struct sockaddr_in saddr; + struct sockaddr_in daddr; +}; + + + +/* + send a gratuitous arp + */ +static void ctdb_control_send_arp(struct event_context *ev, struct timed_event *te, + struct timeval t, void *private_data) +{ + struct ctdb_takeover_arp *arp = talloc_get_type(private_data, + struct ctdb_takeover_arp); + int ret; + struct ctdb_tcp_list *tcp; + + ret = ctdb_sys_send_arp(&arp->sin, arp->ctdb->takeover.interface); + if (ret != 0) { + DEBUG(0,(__location__ "sending of arp failed (%s)\n", strerror(errno))); + } + + for (tcp=arp->tcp_list;tcp;tcp=tcp->next) { + DEBUG(2,("sending tcp tickle ack for %u->%s:%u\n", + (unsigned)ntohs(tcp->daddr.sin_port), + inet_ntoa(tcp->saddr.sin_addr), + (unsigned)ntohs(tcp->saddr.sin_port))); + ret = ctdb_sys_send_ack(&tcp->saddr, &tcp->daddr); + if (ret != 0) { + DEBUG(0,(__location__ " Failed to send tcp tickle ack for %s\n", + inet_ntoa(tcp->saddr.sin_addr))); + } + } + + arp->count++; + + if (arp->count == CTDB_ARP_REPEAT) { + talloc_free(arp); + return; + } + + event_add_timed(arp->ctdb->ev, arp->ctdb->takeover.last_ctx, + timeval_current_ofs(CTDB_ARP_INTERVAL, 0), + ctdb_control_send_arp, arp); +} + + +/* + take over an ip address + */ +int32_t ctdb_control_takeover_ip(struct ctdb_context *ctdb, TDB_DATA indata) +{ + int ret; + struct sockaddr_in *sin = (struct sockaddr_in *)indata.dptr; + struct ctdb_takeover_arp *arp; + char *ip = inet_ntoa(sin->sin_addr); + struct ctdb_tcp_list *tcp; + + if (ctdb_sys_have_ip(ip)) { + return 0; + } + + DEBUG(0,("Takover of IP %s/%u on interface %s\n", + ip, ctdb->nodes[ctdb->vnn]->public_netmask_bits, + ctdb->takeover.interface)); + ret = ctdb_event_script(ctdb, "takeip %s %s %u", + ctdb->takeover.interface, + ip, + ctdb->nodes[ctdb->vnn]->public_netmask_bits); + if (ret != 0) { + DEBUG(0,(__location__ " Failed to takeover IP %s on interface %s\n", + ip, ctdb->takeover.interface)); + return -1; + } + + if (!ctdb->takeover.last_ctx) { + ctdb->takeover.last_ctx = talloc_new(ctdb); + CTDB_NO_MEMORY(ctdb, ctdb->takeover.last_ctx); + } + + arp = talloc_zero(ctdb->takeover.last_ctx, struct ctdb_takeover_arp); + CTDB_NO_MEMORY(ctdb, arp); + + arp->ctdb = ctdb; + arp->sin = *sin; + + /* add all of the known tcp connections for this IP to the + list of tcp connections to send tickle acks for */ + for (tcp=ctdb->tcp_list;tcp;tcp=tcp->next) { + if (sin->sin_addr.s_addr == tcp->daddr.sin_addr.s_addr) { + struct ctdb_tcp_list *t2 = talloc(arp, struct ctdb_tcp_list); + CTDB_NO_MEMORY(ctdb, t2); + *t2 = *tcp; + DLIST_ADD(arp->tcp_list, t2); + } + } + + event_add_timed(arp->ctdb->ev, arp->ctdb->takeover.last_ctx, + timeval_zero(), ctdb_control_send_arp, arp); + + return ret; +} + +/* + release an ip address + */ +int32_t ctdb_control_release_ip(struct ctdb_context *ctdb, TDB_DATA indata) +{ + struct sockaddr_in *sin = (struct sockaddr_in *)indata.dptr; + TDB_DATA data; + char *ip = inet_ntoa(sin->sin_addr); + int ret; + struct ctdb_tcp_list *tcp; + + if (!ctdb_sys_have_ip(ip)) { + return 0; + } + + DEBUG(0,("Release of IP %s/%u on interface %s\n", + ip, ctdb->nodes[ctdb->vnn]->public_netmask_bits, + ctdb->takeover.interface)); + + /* stop any previous arps */ + talloc_free(ctdb->takeover.last_ctx); + ctdb->takeover.last_ctx = NULL; + + ret = ctdb_event_script(ctdb, "releaseip %s %s %u", + ctdb->takeover.interface, + ip, + ctdb->nodes[ctdb->vnn]->public_netmask_bits); + if (ret != 0) { + DEBUG(0,(__location__ " Failed to release IP %s on interface %s\n", + ip, ctdb->takeover.interface)); + return -1; + } + + /* send a message to all clients of this node telling them + that the cluster has been reconfigured and they should + release any sockets on this IP */ + data.dptr = (uint8_t *)ip; + data.dsize = strlen(ip)+1; + + ctdb_daemon_send_message(ctdb, ctdb->vnn, CTDB_SRVID_RELEASE_IP, data); + + /* tell other nodes about any tcp connections we were holding with this IP */ + for (tcp=ctdb->tcp_list;tcp;tcp=tcp->next) { + if (tcp->vnn == ctdb->vnn && + sin->sin_addr.s_addr == tcp->daddr.sin_addr.s_addr) { + struct ctdb_control_tcp_vnn t; + + t.vnn = ctdb->vnn; + t.src = tcp->saddr; + t.dest = tcp->daddr; + + data.dptr = (uint8_t *)&t; + data.dsize = sizeof(t); + + ctdb_daemon_send_control(ctdb, CTDB_BROADCAST_VNNMAP, 0, + CTDB_CONTROL_TCP_ADD, + 0, CTDB_CTRL_FLAG_NOREPLY, data, NULL, NULL); + } + } + + + return 0; +} + + +/* + setup the event script +*/ +int ctdb_set_event_script(struct ctdb_context *ctdb, const char *script) +{ + ctdb->takeover.event_script = talloc_strdup(ctdb, script); + CTDB_NO_MEMORY(ctdb, ctdb->takeover.event_script); + return 0; +} + +/* + setup the public address list from a file +*/ +int ctdb_set_public_addresses(struct ctdb_context *ctdb, const char *alist) +{ + char **lines; + int nlines; + int i; + + lines = file_lines_load(alist, &nlines, ctdb); + if (lines == NULL) { + ctdb_set_error(ctdb, "Failed to load public address list '%s'\n", alist); + return -1; + } + while (nlines > 0 && strcmp(lines[nlines-1], "") == 0) { + nlines--; + } + + if (nlines != ctdb->num_nodes) { + DEBUG(0,("Number of lines in %s does not match number of nodes!\n", alist)); + talloc_free(lines); + return -1; + } + + for (i=0;i<nlines;i++) { + char *p; + struct in_addr in; + + ctdb->nodes[i]->public_address = talloc_strdup(ctdb->nodes[i], lines[i]); + CTDB_NO_MEMORY(ctdb, ctdb->nodes[i]->public_address); + ctdb->nodes[i]->takeover_vnn = -1; + + /* see if they supplied a netmask length */ + p = strchr(ctdb->nodes[i]->public_address, '/'); + if (!p) { + DEBUG(0,("You must supply a netmask for public address %s\n", + ctdb->nodes[i]->public_address)); + return -1; + } + *p = 0; + ctdb->nodes[i]->public_netmask_bits = atoi(p+1); + + if (ctdb->nodes[i]->public_netmask_bits > 32) { + DEBUG(0, ("Illegal netmask for IP %s\n", ctdb->nodes[i]->public_address)); + return -1; + } + + if (inet_aton(ctdb->nodes[i]->public_address, &in) == 0) { + DEBUG(0,("Badly formed IP '%s' in public address list\n", ctdb->nodes[i]->public_address)); + return -1; + } + } + + talloc_free(lines); + return 0; +} + +/* + see if two IPs are on the same subnet + */ +static bool ctdb_same_subnet(const char *ip1, const char *ip2, uint8_t netmask_bits) +{ + struct in_addr in1, in2; + uint32_t mask; + + inet_aton(ip1, &in1); + inet_aton(ip2, &in2); + + mask = ~((1LL<<(32-netmask_bits))-1); + + if ((ntohl(in1.s_addr) & mask) != (ntohl(in2.s_addr) & mask)) { + return false; + } + + return true; +} + +/* + make any IP alias changes for public addresses that are necessary + */ +int ctdb_takeover_run(struct ctdb_context *ctdb, struct ctdb_node_map *nodemap) +{ + int i, j; + int ret; + + /* work out which node will look after each public IP */ + for (i=0;i<nodemap->num;i++) { + if (nodemap->nodes[i].flags & NODE_FLAGS_CONNECTED) { + ctdb->nodes[i]->takeover_vnn = nodemap->nodes[i].vnn; + } else { + /* assign this dead nodes IP to the next higher node */ + for (j=(i+1)%nodemap->num; + j != i; + j=(j+1)%nodemap->num) { + if ((nodemap->nodes[j].flags & NODE_FLAGS_CONNECTED) && + ctdb_same_subnet(ctdb->nodes[j]->public_address, + ctdb->nodes[i]->public_address, + ctdb->nodes[j]->public_netmask_bits)) { + ctdb->nodes[i]->takeover_vnn = nodemap->nodes[j].vnn; + break; + } + } + if (j == i) { + DEBUG(0,(__location__ " No node available on same network to take %s\n", + ctdb->nodes[i]->public_address)); + ctdb->nodes[i]->takeover_vnn = -1; + } + } + } + + /* at this point ctdb->nodes[i]->takeover_vnn is the vnn which will own each IP */ + + + /* now tell all nodes to delete any alias that they should not + have. This will be a NOOP on nodes that don't currently + hold the given alias */ + for (i=0;i<nodemap->num;i++) { + /* don't talk to unconnected nodes */ + if (!(nodemap->nodes[i].flags & NODE_FLAGS_CONNECTED)) continue; + + /* tell this node to delete all of the aliases that it should not have */ + for (j=0;j<nodemap->num;j++) { + if (ctdb->nodes[j]->takeover_vnn != nodemap->nodes[i].vnn) { + ret = ctdb_ctrl_release_ip(ctdb, TAKEOVER_TIMEOUT(), + nodemap->nodes[i].vnn, + ctdb->nodes[j]->public_address); + if (ret != 0) { + DEBUG(0,("Failed to tell vnn %u to release IP %s\n", + nodemap->nodes[i].vnn, + ctdb->nodes[j]->public_address)); + return -1; + } + } + } + } + + /* tell all nodes to get their own IPs */ + for (i=0;i<nodemap->num;i++) { + ret = ctdb_ctrl_takeover_ip(ctdb, TAKEOVER_TIMEOUT(), + ctdb->nodes[i]->takeover_vnn, + ctdb->nodes[i]->public_address); + if (ret != 0) { + DEBUG(0,("Failed asking vnn %u to take over IP %s\n", + ctdb->nodes[i]->takeover_vnn, + ctdb->nodes[i]->public_address)); + return -1; + } + } + + return 0; +} + + +/* + called by a client to inform us of a TCP connection that it is managing + that should tickled with an ACK when IP takeover is done + */ +int32_t ctdb_control_tcp_client(struct ctdb_context *ctdb, uint32_t client_id, uint32_t vnn, + TDB_DATA indata) +{ + struct ctdb_client *client = ctdb_reqid_find(ctdb, client_id, struct ctdb_client); + struct ctdb_control_tcp *p = (struct ctdb_control_tcp *)indata.dptr; + struct ctdb_tcp_list *tcp; + struct ctdb_control_tcp_vnn t; + int ret; + TDB_DATA data; + + tcp = talloc(client, struct ctdb_tcp_list); + CTDB_NO_MEMORY(ctdb, tcp); + + tcp->vnn = vnn; + tcp->saddr = p->src; + tcp->daddr = p->dest; + + DLIST_ADD(client->tcp_list, tcp); + + t.vnn = vnn; + t.src = p->src; + t.dest = p->dest; + + data.dptr = (uint8_t *)&t; + data.dsize = sizeof(t); + + /* tell all nodes about this tcp connection */ + ret = ctdb_daemon_send_control(ctdb, CTDB_BROADCAST_VNNMAP, 0, + CTDB_CONTROL_TCP_ADD, + 0, CTDB_CTRL_FLAG_NOREPLY, data, NULL, NULL); + if (ret != 0) { + DEBUG(0,(__location__ " Failed to send CTDB_CONTROL_TCP_ADD\n")); + return -1; + } + + return 0; +} + +/* + see if two sockaddr_in are the same + */ +static bool same_sockaddr_in(struct sockaddr_in *in1, struct sockaddr_in *in2) +{ + return in1->sin_family == in2->sin_family && + in1->sin_port == in2->sin_port && + in1->sin_addr.s_addr == in2->sin_addr.s_addr; +} + +/* + find a tcp address on a list + */ +static struct ctdb_tcp_list *ctdb_tcp_find(struct ctdb_tcp_list *list, + struct ctdb_tcp_list *tcp) +{ + while (list) { + if (same_sockaddr_in(&list->saddr, &tcp->saddr) && + same_sockaddr_in(&list->daddr, &tcp->daddr)) { + return list; + } + list = list->next; + } + return NULL; +} + +/* + called by a daemon to inform us of a TCP connection that one of its + clients managing that should tickled with an ACK when IP takeover is + done + */ +int32_t ctdb_control_tcp_add(struct ctdb_context *ctdb, TDB_DATA indata) +{ + struct ctdb_control_tcp_vnn *p = (struct ctdb_control_tcp_vnn *)indata.dptr; + struct ctdb_tcp_list *tcp; + + tcp = talloc(ctdb, struct ctdb_tcp_list); + CTDB_NO_MEMORY(ctdb, tcp); + + tcp->vnn = p->vnn; + tcp->saddr = p->src; + tcp->daddr = p->dest; + + if (NULL == ctdb_tcp_find(ctdb->tcp_list, tcp)) { + DLIST_ADD(ctdb->tcp_list, tcp); + DEBUG(2,("Added tickle info for %s:%u from vnn %u\n", + inet_ntoa(tcp->daddr.sin_addr), ntohs(tcp->daddr.sin_port), + tcp->vnn)); + } else { + DEBUG(4,("Already had tickle info for %s:%u from vnn %u\n", + inet_ntoa(tcp->daddr.sin_addr), ntohs(tcp->daddr.sin_port), + tcp->vnn)); + } + + return 0; +} + +/* + called by a daemon to inform us of a TCP connection that one of its + clients managing that should tickled with an ACK when IP takeover is + done + */ +int32_t ctdb_control_tcp_remove(struct ctdb_context *ctdb, TDB_DATA indata) +{ + struct ctdb_control_tcp_vnn *p = (struct ctdb_control_tcp_vnn *)indata.dptr; + struct ctdb_tcp_list t, *tcp; + + t.vnn = p->vnn; + t.saddr = p->src; + t.daddr = p->dest; + + tcp = ctdb_tcp_find(ctdb->tcp_list, &t); + if (tcp) { + DEBUG(2,("Removed tickle info for %s:%u from vnn %u\n", + inet_ntoa(tcp->daddr.sin_addr), ntohs(tcp->daddr.sin_port), + tcp->vnn)); + DLIST_REMOVE(ctdb->tcp_list, tcp); + talloc_free(tcp); + } + + return 0; +} + + +/* + called when a daemon restarts - wipes all tcp entries from that vnn + */ +int32_t ctdb_control_startup(struct ctdb_context *ctdb, uint32_t vnn) +{ + struct ctdb_tcp_list *tcp, *next; + for (tcp=ctdb->tcp_list;tcp;tcp=next) { + next = tcp->next; + if (tcp->vnn == vnn) { + DLIST_REMOVE(ctdb->tcp_list, tcp); + talloc_free(tcp); + } + + /* and tell the new guy about any that he should have + from us */ + if (tcp->vnn == ctdb->vnn) { + struct ctdb_control_tcp_vnn t; + TDB_DATA data; + + t.vnn = tcp->vnn; + t.src = tcp->saddr; + t.dest = tcp->daddr; + + data.dptr = (uint8_t *)&t; + data.dsize = sizeof(t); + + ctdb_daemon_send_control(ctdb, vnn, 0, + CTDB_CONTROL_TCP_ADD, + 0, CTDB_CTRL_FLAG_NOREPLY, data, NULL, NULL); + } + } + return 0; +} + + +/* + called when a client structure goes away - hook to remove + elements from the tcp_list in all daemons + */ +void ctdb_takeover_client_destructor_hook(struct ctdb_client *client) +{ + while (client->tcp_list) { + TDB_DATA data; + struct ctdb_control_tcp_vnn p; + struct ctdb_tcp_list *tcp = client->tcp_list; + DLIST_REMOVE(client->tcp_list, tcp); + p.vnn = tcp->vnn; + p.src = tcp->saddr; + p.dest = tcp->daddr; + data.dptr = (uint8_t *)&p; + data.dsize = sizeof(p); + ctdb_daemon_send_control(client->ctdb, CTDB_BROADCAST_VNNMAP, 0, + CTDB_CONTROL_TCP_REMOVE, + 0, CTDB_CTRL_FLAG_NOREPLY, data, NULL, NULL); + talloc_free(tcp); + } +} + + +/* + release all IPs on shutdown + */ +void ctdb_release_all_ips(struct ctdb_context *ctdb) +{ + int i; + + if (!ctdb->takeover.enabled) { + return; + } + + for (i=0;i<ctdb->num_nodes;i++) { + struct ctdb_node *node = ctdb->nodes[i]; + if (ctdb_sys_have_ip(node->public_address)) { + ctdb_event_script(ctdb, "releaseip %s %s %u", + ctdb->takeover.interface, + node->public_address, + node->public_netmask_bits); + } + } +} |