1 files changed, 45 insertions, 0 deletions
diff --git a/doc/developer/logging.rst b/doc/developer/logging.rst
index e262f6af9..231ef37d4 100644
--- a/doc/developer/logging.rst
+++ b/doc/developer/logging.rst
@@ -502,6 +502,51 @@ General utility formats
    representation for a hexdump.  Non-printable characters are replaced with
    a dot.
 
+.. frrfmt:: %pIS (struct iso_address *)
+
+   ([IS]o Network address) - Format ISO Network Address
+
+   ``%pIS``: :frrfmtout:`01.0203.04O5`
+   ISO Network address is printed as separated byte. The number of byte of the
+   address is embeded in the `iso_net` structure.
+
+   ``%pISl``: :frrfmtout:`01.0203.04O5.0607.0809.1011.1213.14` - long format to
+   print the long version of the ISO Network address which include the System
+   ID and the PSEUDO-ID of the IS-IS system
+
+   Note that the `ISO_ADDR_STRLEN` define gives the total size of the string
+   that could be used in conjunction to snprintfrr. Use like::
+
+     char buf[ISO_ADDR_STRLEN];
+     struct iso_net addr = {.len = 4, .addr = {1, 2, 3, 4}};
+     snprintfrr(buf, ISO_ADDR_STRLEN, "%pIS", &addr);
+
+.. frrfmt:: %pSY (uint8_t *)
+
+   (IS-IS [SY]stem ID) - Format IS-IS System ID
+
+   ``%pSY``: :frrfmtout:`0102.0304.0506`
+
+.. frrfmt:: %pPN (uint8_t *)
+
+   (IS-IS [P]seudo [N]ode System ID) - Format IS-IS Pseudo Node System ID
+
+   ``%pPN``: :frrfmtout:`0102.0304.0506.07`
+
+.. frrfmt:: %pLS (uint8_t *)
+
+   (IS-IS [L]sp fragment [S]ystem ID) - Format IS-IS Pseudo System ID
+
+   ``%pLS``: :frrfmtout:`0102.0304.0506.07-08`
+
+   Note that the `ISO_SYSID_STRLEN` define gives the total size of the string
+   that could be used in conjunction to snprintfrr. Use like::
+
+     char buf[ISO_SYSID_STRLEN];
+     uint8_t id[8] = {1, 2, 3, 4 , 5 , 6 , 7, 8};
+     snprintfrr(buf, SYS_ID_SIZE, "%pSY", id);
+
+
 Integer formats
 ^^^^^^^^^^^^^^^