Re: [PATCH] MINOR: dns: Set maximum DNS udp payload at 65507
Hi, Any news on this? We have use cases with records returning 600+ IPs and the resolution fails since it exceeds the payload. Regards, Anthonin On Sun, Dec 2, 2018 at 6:46 PM Willy Tarreau wrote: > On Thu, Oct 18, 2018 at 05:52:47PM +0200, Anthonin Bonnefoy wrote: > > From: Anthonin Bonnefoy > > > > With EDNS, DNS packets can have a maximum size of 65507. > > This will allow to have a bigger accepted_payload_size which is useful > > when we have more than 100 SRV records. > > Baptiste, please have a look at this one, I want to be sure we don't > miss it if needed. > > Thanks, > Willy > > > --- > > include/types/dns.h | 5 - > > 1 file changed, 4 insertions(+), 1 deletion(-) > > > > diff --git a/include/types/dns.h b/include/types/dns.h > > index 488d3996..53f24c19 100644 > > --- a/include/types/dns.h > > +++ b/include/types/dns.h > > @@ -42,7 +42,10 @@ > > */ > > #define DNS_MAX_LABEL_SIZE 63 > > #define DNS_MAX_NAME_SIZE255 > > -#define DNS_MAX_UDP_MESSAGE 8192 > > +/* With EDNS, DNS message can reach the maximum size of an UDP message > > + * which is (65535 - 8 bytes UDP header - 20 bytes IP header) > > + */ > > +#define DNS_MAX_UDP_MESSAGE 65507 > > > > /* DNS minimun record size: 1 char + 1 NULL + type + class */ > > #define DNS_MIN_RECORD_SIZE (1 + 1 + 2 + 2) > > -- > > 2.13.2 > > >
Re: [PATCH] MINOR: dns: Set maximum DNS udp payload at 65507
On Thu, Oct 18, 2018 at 05:52:47PM +0200, Anthonin Bonnefoy wrote: > From: Anthonin Bonnefoy > > With EDNS, DNS packets can have a maximum size of 65507. > This will allow to have a bigger accepted_payload_size which is useful > when we have more than 100 SRV records. Baptiste, please have a look at this one, I want to be sure we don't miss it if needed. Thanks, Willy > --- > include/types/dns.h | 5 - > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/include/types/dns.h b/include/types/dns.h > index 488d3996..53f24c19 100644 > --- a/include/types/dns.h > +++ b/include/types/dns.h > @@ -42,7 +42,10 @@ > */ > #define DNS_MAX_LABEL_SIZE 63 > #define DNS_MAX_NAME_SIZE255 > -#define DNS_MAX_UDP_MESSAGE 8192 > +/* With EDNS, DNS message can reach the maximum size of an UDP message > + * which is (65535 - 8 bytes UDP header - 20 bytes IP header) > + */ > +#define DNS_MAX_UDP_MESSAGE 65507 > > /* DNS minimun record size: 1 char + 1 NULL + type + class */ > #define DNS_MIN_RECORD_SIZE (1 + 1 + 2 + 2) > -- > 2.13.2 >
[PATCH] MINOR: dns: Set maximum DNS udp payload at 65507
From: Anthonin Bonnefoy With EDNS, DNS packets can have a maximum size of 65507. This will allow to have a bigger accepted_payload_size which is useful when we have more than 100 SRV records. --- include/types/dns.h | 5 - 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/include/types/dns.h b/include/types/dns.h index 488d3996..53f24c19 100644 --- a/include/types/dns.h +++ b/include/types/dns.h @@ -42,7 +42,10 @@ */ #define DNS_MAX_LABEL_SIZE 63 #define DNS_MAX_NAME_SIZE255 -#define DNS_MAX_UDP_MESSAGE 8192 +/* With EDNS, DNS message can reach the maximum size of an UDP message + * which is (65535 - 8 bytes UDP header - 20 bytes IP header) + */ +#define DNS_MAX_UDP_MESSAGE 65507 /* DNS minimun record size: 1 char + 1 NULL + type + class */ #define DNS_MIN_RECORD_SIZE (1 + 1 + 2 + 2) -- 2.13.2