Instalacion CERO de server DESA siu guarani

Gracias Florencia.

Volví a la version de Composer “1.10.15” ( como bien menciona en link que me pasaste ) y ahora me arroja los siguientes probelmas :

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$ php composer.phar install
PHP Warning: Module ‘PDO’ already loaded in Unknown on line 0
PHP Warning: Module ‘pdo_pgsql’ already loaded in Unknown on line 0
Loading composer repositories with package information
Updating dependencies (including require-dev)
Your requirements could not be resolved to an installable set of packages.

Problem 1
- siu-toba/framework v3.3.9 requires php >=7.3 → your PHP version (7.1.33) does not satisfy that requirement.
- siu-toba/framework v3.3.8 requires php >=7.3 → your PHP version (7.1.33) does not satisfy that requirement.
- siu-toba/framework v3.3.7 requires php >=7.3 → your PHP version (7.1.33) does not satisfy that requirement.
- siu-toba/framework v3.3.6 requires php >=7.3 → your PHP version (7.1.33) does not satisfy that requirement.
- siu-toba/framework v3.3.5 requires php >=7.3 → your PHP version (7.1.33) does not satisfy that requirement.
- siu-toba/framework v3.3.4 requires php >=7.3 → your PHP version (7.1.33) does not satisfy that requirement.
- siu-toba/framework v3.3.3 requires php >=7.3 → your PHP version (7.1.33) does not satisfy that requirement.
- siu-toba/framework v3.3.2 requires php >=7.3 → your PHP version (7.1.33) does not satisfy that requirement.
- siu-toba/framework v3.3.13 requires php >=7.3 → your PHP version (7.1.33) does not satisfy that requirement.
- siu-toba/framework v3.3.12 requires php >=7.3 → your PHP version (7.1.33) does not satisfy that requirement.
- siu-toba/framework v3.3.11 requires php >=7.3 → your PHP version (7.1.33) does not satisfy that requirement.
- siu-toba/framework v3.3.10 requires php >=7.3 → your PHP version (7.1.33) does not satisfy that requirement.
- siu-toba/framework v3.3.1 requires php >=7.3 → your PHP version (7.1.33) does not satisfy that requirement.
- siu-toba/framework v3.3.0 requires php >=7.3 → your PHP version (7.1.33) does not satisfy that requirement.
- siu-toba/framework v3.1.9 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.1.8 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.1.7 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.1.6 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.1.5 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.1.4 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.1.3 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.1.2 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.1.15 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.1.14 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.1.12 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.1.11 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.1.10 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.1.1 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.1.0 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.9 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.8 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.7 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.6 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.5 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.4 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.32 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.31 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.30 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.3 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.29 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.28 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.27 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.26 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.25 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.24 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.23 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.22 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.21 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.20 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.2 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.19 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.18 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.17 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.16 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.15 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.14 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.13 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.12 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.11 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.10 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.0.0 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework 3.1.13 requires ircmaxell/random-lib dev-master → no matching package found.
- siu/security-multitool v1.0 requires ircmaxell/random-lib dev-master@dev → no matching package found.
- siu-toba/framework 3.0.1 requires ircmaxell/random-lib dev-master → no matching package found.
- siu-toba/framework v3.1.16 conflicts with siu/arai-cli[v2.4.0].
- siu-toba/framework v3.1.17 conflicts with siu/arai-cli[v2.4.0].
- siu-toba/framework v3.2.12 conflicts with siu/arai-cli[v2.4.0].
- siu-toba/framework v3.2.13 conflicts with siu/arai-cli[v2.4.0].
- siu-toba/framework v3.2.14 conflicts with siu/arai-cli[v2.4.0].
- siu-toba/framework v3.2.15 conflicts with siu/arai-cli[v2.4.0].
- siu-toba/framework v3.2.16 conflicts with siu/arai-cli[v2.4.0].
- siu-toba/framework v3.2.17 conflicts with siu/arai-cli[v2.4.0].
- siu-toba/framework v3.2.18 conflicts with siu/arai-cli[v2.4.0].
- siu-toba/framework v3.2.0 requires siu/security-multitool 1.0 → satisfiable by siu/security-multitool[v1.0].
- siu-toba/framework v3.2.1 requires siu/security-multitool 1.0 → satisfiable by siu/security-multitool[v1.0].
- siu-toba/framework v3.2.10 requires siu/security-multitool 1.0 → satisfiable by siu/security-multitool[v1.0].
- siu-toba/framework v3.2.11 requires siu/security-multitool 1.0 → satisfiable by siu/security-multitool[v1.0].
- siu-toba/framework v3.2.2 requires siu/security-multitool 1.0 → satisfiable by siu/security-multitool[v1.0].
- siu-toba/framework v3.2.3 requires siu/security-multitool 1.0 → satisfiable by siu/security-multitool[v1.0].
- siu-toba/framework v3.2.4 requires siu/security-multitool 1.0 → satisfiable by siu/security-multitool[v1.0].
- siu-toba/framework v3.2.5 requires siu/security-multitool 1.0 → satisfiable by siu/security-multitool[v1.0].
- siu-toba/framework v3.2.6 requires siu/security-multitool 1.0 → satisfiable by siu/security-multitool[v1.0].
- siu-toba/framework v3.2.7 requires siu/security-multitool 1.0 → satisfiable by siu/security-multitool[v1.0].
- siu-toba/framework v3.2.8 requires siu/security-multitool 1.0 → satisfiable by siu/security-multitool[v1.0].
- siu-toba/framework v3.2.9 requires siu/security-multitool 1.0 → satisfiable by siu/security-multitool[v1.0].
- Installation request for siu/arai-cli 2.4.0 → satisfiable by siu/arai-cli[v2.4.0].
- Installation request for siu-toba/framework ^3.0 → satisfiable by siu-toba/framework[3.0.1, 3.1.13, v3.0.0, v3.0.10, v3.0.11, v3.0.12, v3.0.13, v3.0.14, v3.0.15, v3.0.16, v3.0.17, v3.0.18, v3.0.19, v3.0.2, v3.0.20, v3.0.21, v3.0.22, v3.0.23, v3.0.24, v3.0.25, v3.0.26, v3.0.27, v3.0.28, v3.0.29, v3.0.3, v3.0.30, v3.0.31, v3.0.32, v3.0.4, v3.0.5, v3.0.6, v3.0.7, v3.0.8, v3.0.9, v3.1.0, v3.1.1, v3.1.10, v3.1.11, v3.1.12, v3.1.14, v3.1.15, v3.1.16, v3.1.17, v3.1.2, v3.1.3, v3.1.4, v3.1.5, v3.1.6, v3.1.7, v3.1.8, v3.1.9, v3.2.0, v3.2.1, v3.2.10, v3.2.11, v3.2.12, v3.2.13, v3.2.14, v3.2.15, v3.2.16, v3.2.17, v3.2.18, v3.2.2, v3.2.3, v3.2.4, v3.2.5, v3.2.6, v3.2.7, v3.2.8, v3.2.9, v3.3.0, v3.3.1, v3.3.10, v3.3.11, v3.3.12, v3.3.13, v3.3.2, v3.3.3, v3.3.4, v3.3.5, v3.3.6, v3.3.7, v3.3.8, v3.3.9].

Potential causes:

Read https://getcomposer.org/doc/articles/troubleshooting.md for further common problems.
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¿Tengo que instalar PHP 7.3 ? Según la documentación, con 7.1 era suficiente.

Aguardo respuesta.

Muchas gracias,
Patricio.