Thanks for the patch. I'm not sure in what circumstances a broadcast domain would be shared among deployments. I tend to think of OVN L2 networks as contained. But I guess this patch was written for a reason, so it must be common enough.
I can see at least two possible routes here: - The current one, in which there is a default MAC_ADDR_PREFIX. Two OVN deployments cannot coexist using MACAM, supposing they somehow share a broadcast domain, unless at least one of them manually selects an alternate MAC prefix. This may be desirable if it is important that the default MAC prefix 0A-00-00 be recognizable. - An alternative would be for every OVN deployment to automatically select a random MAC address prefix. When ovn-northd starts, it would read the MAC address prefix out of NB_Global, and if there isn't one, generate one randomly and store it into NB_Global. Then there would be fewer pitfalls in setting up multiple deployments. I am OK with the one currently proposed, but I want to make sure that the other approach was at least considered. On Fri, Oct 26, 2018 at 04:15:27PM -0400, Mark Michelson wrote: > Looks good, Lorenzo, > > Just to reaaffirm my previous ack: > > Acked-by: Mark Michelson <mmich...@redhat.com> > > On 10/26/2018 12:20 PM, Lorenzo Bianconi wrote: > >Add the possibility to specify a given mac address prefix for > >dynamically generated mac address. Mac address prefix can be > >specified in nbdb NB_Global table, options:mac_prefix=<mac_prefix> > >This patch fix a possible issue of L2 address duplication if > >multiple OVN deployments share a single broadcast domain > > > >Acked-by: Mark Michelson <mmich...@redhat.com> > >Signed-off-by: Lorenzo Bianconi <lorenzo.bianc...@redhat.com> > >--- > >Changes since v1: > >- use a global definition for mac_prefix > >--- > > ovn/northd/ovn-northd.c | 37 ++++++++++++++++++++++++++++++++++--- > > ovn/ovn-nb.xml | 5 +++++ > > tests/ovn.at | 17 +++++++++++++++++ > > 3 files changed, 56 insertions(+), 3 deletions(-) > > > >diff --git a/ovn/northd/ovn-northd.c b/ovn/northd/ovn-northd.c > >index 439651f80..816c72311 100644 > >--- a/ovn/northd/ovn-northd.c > >+++ b/ovn/northd/ovn-northd.c > >@@ -68,6 +68,7 @@ static const char *unixctl_path; > > /* MAC address management (macam) table of "struct eth_addr"s, that holds > > the > > * MAC addresses allocated by the OVN ipam module. */ > > static struct hmap macam = HMAP_INITIALIZER(&macam); > >+static struct eth_addr mac_prefix; > > #define MAX_OVN_TAGS 4096 > > > >@@ -922,10 +923,17 @@ ipam_insert_mac(struct eth_addr *ea, bool check) > > } > > uint64_t mac64 = eth_addr_to_uint64(*ea); > >+ uint64_t prefix; > >+ > >+ if (!eth_addr_is_zero(mac_prefix)) { > >+ prefix = eth_addr_to_uint64(mac_prefix); > >+ } else { > >+ prefix = MAC_ADDR_PREFIX; > >+ } > > /* If the new MAC was not assigned by this address management system or > > * check is true and the new MAC is a duplicate, do not insert it into > > the > > * macam hmap. */ > >- if (((mac64 ^ MAC_ADDR_PREFIX) >> 24) > >+ if (((mac64 ^ prefix) >> 24) > > || (check && ipam_is_duplicate_mac(ea, mac64, true))) { > > return; > > } > >@@ -1036,7 +1044,11 @@ ipam_get_unused_mac(void) > > for (i = 0; i < MAC_ADDR_SPACE - 1; i++) { > > /* The tentative MAC's suffix will be in the interval (1, > > 0xfffffe). */ > > mac_addr_suffix = ((last_mac + i) % (MAC_ADDR_SPACE - 1)) + 1; > >- mac64 = MAC_ADDR_PREFIX | mac_addr_suffix; > >+ if (!eth_addr_is_zero(mac_prefix)) { > >+ mac64 = eth_addr_to_uint64(mac_prefix) | mac_addr_suffix; > >+ } else { > >+ mac64 = MAC_ADDR_PREFIX | mac_addr_suffix; > >+ } > > eth_addr_from_uint64(mac64, &mac); > > if (!ipam_is_duplicate_mac(&mac, mac64, false)) { > > last_mac = mac_addr_suffix; > >@@ -1107,7 +1119,15 @@ dynamic_mac_changed(const char *lsp_addresses, > > } > > uint64_t mac64 = eth_addr_to_uint64(update->current_addresses.ea); > >- if ((mac64 ^ MAC_ADDR_PREFIX) >> 24) { > >+ uint64_t prefix; > >+ > >+ if (!eth_addr_is_zero(mac_prefix)) { > >+ prefix = eth_addr_to_uint64(mac_prefix); > >+ } else { > >+ prefix = MAC_ADDR_PREFIX; > >+ } > >+ > >+ if ((mac64 ^ prefix) >> 24) { > > return DYNAMIC; > > } else { > > return NONE; > >@@ -7141,6 +7161,17 @@ ovnnb_db_run(struct northd_context *ctx, > > sbrec_sb_global_set_options(sb, &nb->options); > > sb_loop->next_cfg = nb->nb_cfg; > >+ const char *mac_addr_prefix = smap_get(&nb->options, "mac_prefix"); > >+ if (mac_addr_prefix) { > >+ struct eth_addr addr; > >+ > >+ memset(&addr, 0, sizeof addr); > >+ if (ovs_scan(mac_addr_prefix, "%"SCNx8":%"SCNx8":%"SCNx8, > >+ &addr.ea[0], &addr.ea[1], &addr.ea[2])) { > >+ mac_prefix = addr; > >+ } > >+ } > >+ > > cleanup_macam(&macam); > > } > >diff --git a/ovn/ovn-nb.xml b/ovn/ovn-nb.xml > >index c0739fe57..f309b3b86 100644 > >--- a/ovn/ovn-nb.xml > >+++ b/ovn/ovn-nb.xml > >@@ -102,6 +102,11 @@ > > tunnel interfaces. > > </column> > > </group> > >+ > >+ <column name="options" key="mac_prefix"> > >+ Configure a given OUI to be used as prefix when L2 address is > >+ dynamically assigned, e.g. <code>00:11:22</code> > >+ </column> > > </group> > > <group title="Connection Options"> > >diff --git a/tests/ovn.at b/tests/ovn.at > >index 8825beca3..e512f94aa 100644 > >--- a/tests/ovn.at > >+++ b/tests/ovn.at > >@@ -5616,6 +5616,23 @@ AT_CHECK([ovn-nbctl get Logical-Switch-Port p41 > >dynamic_addresses], [0], > > ["f0:00:00:00:10:2b 192.168.1.3" > > ]) > >+# define a mac address prefix > >+ovn-nbctl ls-add sw6 > >+ovn-nbctl --wait=hv set NB_Global . options:mac_prefix="00:11:22:33:44:55" > >+ovn-nbctl --wait=sb set Logical-Switch sw6 > >other_config:subnet=192.168.100.0/24 > >+for n in $(seq 1 3); do > >+ ovn-nbctl --wait=sb lsp-add sw6 "p5$n" -- lsp-set-addresses "p5$n" > >dynamic > >+done > >+AT_CHECK([ovn-nbctl get Logical-Switch-Port p51 dynamic_addresses], [0], > >+ ["00:11:22:00:00:4d 192.168.100.2" > >+]) > >+AT_CHECK([ovn-nbctl get Logical-Switch-Port p52 dynamic_addresses], [0], > >+ ["00:11:22:00:00:4e 192.168.100.3" > >+]) > >+AT_CHECK([ovn-nbctl get Logical-Switch-Port p53 dynamic_addresses], [0], > >+ ["00:11:22:00:00:4f 192.168.100.4" > >+]) > >+ > > as ovn-sb > > OVS_APP_EXIT_AND_WAIT([ovsdb-server]) > > > > _______________________________________________ > dev mailing list > d...@openvswitch.org > https://mail.openvswitch.org/mailman/listinfo/ovs-dev _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev